Dissonance

CHAPTER ONE

IT SEEMED LIKE a lousy way to remember someone: two aging strips of wood nailed together in the shape of a cross, stuck into a weed-choked ditch on the side of the road. A name, careful cursive in fading black marker, looped across the middle, and a tattered supermarket bouquet—carnations, daisies, baby’s breath—slumped against the base.

It wasn’t much, but it would be enough.

More than enough, if you asked me. Which no one did.

The two-lane road on the edge of town wasn’t busy, but the curve was surprisingly sharp if you didn’t know to look for it, or didn’t care because you were young and thought you’d live forever. Backpack over my shoulder, I started into the ditch, tromping over prickler weeds and knee-high grasses. The ground squelched under my feet, but I ignored it, listening for the hum that meant I was close.

My phone rang, and I shoved it deeper in my pocket. I’d gotten the most important message just after lunch.

“Del, it’s Dad. I’m sorry to cancel our Walk again, but I’ve got an emergency meeting with the Consort this afternoon. Your mother says your assignment’s due tomorrow, so why don’t you . . .”

I hadn’t bothered listening to the rest. I’d heard it—or a variation of it—enough times. Emergencies were the status quo at my house. There was always a problem my parents needed to fix, a fresh crisis demanding their attention. A situation so important everything else was pushed to the side.

More often than not, I was the “everything else.” But the upside of being ignored is that people forget to tell you no.

Burrs clung to my sweater as I picked my way across the muddy terrain. Clouds blanketed the sky, and the air carried a heavy, earthy scent that signaled more rain to come. With any luck I’d be back before the storm hit.

My assignment was easy enough: Walk to a nearby Echo, locate the trouble spots, Walk home. I’d done it countless times, knew the steps well enough that I didn’t need a chaperone. My parents might disagree, but if they were really worried, they would have made the time to come with, like they were supposed to.

I could handle this on my own.

The problem was, the only person who believed me was my grandfather. When other kids were playing park district soccer or climbing trees, Monty had taken me wandering among a different set of branches—the multiverse, the infinity of worlds spreading out from ours like the limbs of a tree. It was Monty who’d first shown me how a single choice could create two distinct realities—the world we lived in and the road not traveled. He’d shown me how to move between those realities, listening for the unique frequency each was set to, using the sound as a pathway across. I’d grown up with his voice in my ear, whispering the secrets of the multiverse, while the sounds of the Echo worlds rang through me like a bell. He’d taught me more about Walking than I’d ever learned from my parents, my older sister, Addison, or Shaw, my teacher at the Consort.

As far as they were concerned, I needed training. Someone to hold my hand while I took baby steps, when all I wanted was to run.

Today I was free to go as fast and as far as I liked.

I held my hand out, palm down, next to the wooden cross. Instantly I felt a thrumming over my skin, like a harp string roughly plucked. It was the pivot, a gate between realities, a sound so faint only one in a hundred thousand people—literally—could hear it.

There are more than six billion people in the world, but only sixty thousand licensed Walkers. Nine hundred in the greater Chicagoland area. Four of them were in my family, and by summer, I’d be the fifth.

Usually pivots are easier to hear than see, but the air around the memorial trembled like leaves in a high wind. It made sense; the strongest pivots form at places where a choice causes a sudden, significant change, and nothing’s more sudden or significant than an unexpected death.

I eased inside the vibrating pocket of air, the rift expanding around me. The dissonance slid over my skin like a dusting of snow. With each step the noise in my head increased, countless frequencies competing for my attention. A pivot directly connects two worlds, but once you’re inside, you can use it to travel to any other Echo in the multiverse. The trick is knowing what to listen for.

Over breakfast, my mom had played a sample of my target frequency, the one I’d need for today’s Walk. But my assignment could wait for a while.

One foot in the Key World, one inside the pivot, I reached into the fabric of the multiverse, choosing a random thread from the dense, rippling weave. The vibration turned my limbs effervescent, while the air grew heavy as water. I hummed, matching the pitch of the string in my hands. The path cleared, resistance fading along with my vision. Another step, and the pivot went wispy and gray.

Another, and I left behind the rules and disappointments and weight of the old world . . .

. . . and walked directly into oncoming traffic.

CHAPTER TWO

Exercise caution when crossing a pivot, as conditions may prove unexpectedly hazardous.

—Chapter Two, “Navigation,”

Principles and Practices of Cleaving, Year Five

RUSH HOUR SWALLOWED me whole.

Cars whipped by, sending my hair into a blinding tangle. Trucks belched exhaust fumes, and a Harley roared so loudly I fell backward, gravel biting into my palms. The pivot’s buzz was lost in the chaos. I scrambled out of the path of a beat-up Chrysler, nearly losing my backpack beneath the wheels.

Not a single car honked or swerved.

Technically I wasn’t invisible—Echoes could see Walkers once we touched them. Otherwise we hovered on the edges of their peripheral vision, present but not worth noticing. Usually this was a good thing, allowing us to move freely in Echo worlds. Right now it increased my odds of being flattened.

A semi barreled toward me. I fumbled for the pivot with both hands, searching for a string—any string—to use. One sang out and I latched on to it.

The truck blew by, a burst of diesel-scented air slamming into my back as I dashed through the rift.

Nobody ever said Walking was safe. Nobody ever said it was boring, either.

The pavement under my feet was pitted and crumbling, with weeds sprouting up through the cracks. On the opposite side of the parking lot stood a rundown apartment complex, the balconies sagging, stick-on numbers missing from half the units. A low, monotone pitch filled my ears, and I gasped in relief.

Adrenaline pumped through my veins, replacing fear with triumph. Sometimes Walking felt like a drug. The aching anticipation, the quicksilver rush, the craving for more—but it was completely legal. Even better, it was expected. I might not be the Walker my parents wanted; that was Addie’s job. But it was my calling, and my life, and the only thing I ever wanted to do.

Best of all, it was infinite.

You could find an endless number of worlds in a single location. If one Echo didn’t suit you, a few steps and a flick of your fingers would bring you to another. The rush never had to end.

Again and again I crossed the pivot, choosing new frequencies each time. I visited hospitals and strip malls, farmhouses and factories, reveling in the sensation of slipping between worlds. I never stayed long, and it never got old, watching the differences that sprang up, each Echo a unique combination of choices and circumstances.

In every world I left a tiny origami star, no bigger than a quarter. Breadcrumbs, my grandfather called them. A piece of the Key World, left behind to mark the way home. As a child, I’d done it to humor him. Now it was part habit and part superstition, my own private ritual.

My world hopping caught up with me in a forest preserve. A dull ache spread through my skull, and my ears rang with the key change. Time to get to work and head home. I could terrify Eliot with my near miss, find out what new disaster my parents had fixed.

Humming the frequency my mom had given me, I stepped into the rift. The string responded, gaining strength, and I followed it through. The massive oak trees disappeared, and when my vision cleared, the dirt path underfoot had shifted to asphalt. Leaf-strewn grass spread out on either side of me. The clouds parted, late-afternoon sunlight warm on my face. I turned in a slow circle, taking in the changes. A big jump in frequencies, for this world to look so different from ours.

On the other side of the pivot, the roadside memorial flickered like the afterimage when you stare at a bright light for too long.

Then it vanished, only a slight ripple marking where someone had died and the world had split in two.

CHAPTER THREE

Vibrato fractums (commonly called “breaks”) are areas of instability within an Echo and an indicator of significant problems. Direct contact with vibrato fractums should be kept to a minimum.

—Chapter One, “Structure and Formation,”

Principles and Practices of Cleaving, Year Five

ACCORDING TO FAMILY legend, I took my first Walk when I was eight months old—long before my first steps and years before most other kids. Wearing nothing but Pampers and a dimple, I’d crawled through a pivot outside our living room, leaving behind my stuffed panda and my outraged older sister.

Even at four, Addie was a fan of rules, and rule number one in our house was no Walking without an adult. So she fetched our grandfather, Monty, and he came after me.

Addie might have caught me, but Monty brought me back.

My grandfather liked to say it was the first sign I was something special, even among Walkers. Addie said it was the first sign I was going to be a pain in the ass. Everyone agreed it was a sign of things to come. I’d been named the problem child; Addie was the good girl. Sixteen years later, and the labels stuck fast.

I gritted my teeth at the frequency surrounding me. My mom had predicted this world would be mildly off-key, but the wavering pitch was stronger—and more unstable—than expected. At most I could last a couple of hours.

I followed the jogging trail around the perimeter of the park, past the duck pond and the picnic shelter, heading for the playground. It would have been pretty, if the whole Echo didn’t sound so awful. Two guys played Frisbee at the water’s edge, the ebb and flow of their laughter obscured by a screeching that made me wince.

Break by the duck pond. Noted.

For an Echo to sound this unstable, there had to be multiple breaks nearby overtaking the primary frequency. I listened for them, ears straining as I put some distance between me and the Frisbee game.

The wind shifted in the trees, bringing the rich smell of autumn with it. Joggers and cyclists passed by, oblivious to the noise surrounding them, their eyes sliding over me.

The playground teemed with shrieking kids leaping off the monkey bars, going down the slide headfirst, playing freeze tag. Two moms pushed their toddlers on the swings, gossiping about playgroups and marital woes. Distracted and jittery from the discord, I slid a pale purple square of paper from my backpack, creasing and folding until a four-pointed star took shape. As I worked, another noise fought for my attention. More ragged, less musical. Annoying. I looked around.

A little girl, four or five, huddled at the base of a tree, sobbing in the unashamed, exceedingly wet way kids do—snot and tears and misery plastered down her front, her wails nearly as loud as the world’s pitch.

Except for breaks, everything in an Echo, living or dead, should resonate at the same frequency. I moved closer, brushing a hand along the girl’s dimpled elbow, wondering if I’d missed something.

I hadn’t. Her signal matched, which meant she was off-limits. Interacting with her would only make things worse, could actually create a break. Smarter to move along and leave her to her sobfest.

The problem was, touching an Echo—even a stable one—caused them to notice you. The kid snuffled and clutched my sleeve, tipping back her tearstained face to look directly at me.

Once one Echo sees you in their world, they all can. But nobody on the playground was paying attention to either of us. Not a single turned head or furrowed brow. It was easier for people to ignore her than listen to her, and I knew what that was like.

I pried her fingers off my arm. “What’s wrong?”

She scrubbed at her eyes. “I was playing and I saw the ducks and I wanted to show them my balloon. And I went on the grass to show the ducks my balloon and I fell and the string went up and now it’s gone and it was red. And red is my favorite color, but my red balloon is gone.” She spoke in one unbroken rush.

“Your balloon is gone.”

“And it was red,” she wailed, a fresh flow of gunk cascading down her face. She pointed skyward. “See?”

I did see—caught in the tree branches overhead was a bedraggled red balloon. “Can your mom buy you a new one?”

“Mommy went to work. I came with Shelby.”

“Shelby?” The little girl pointed to a bored-looking brunette Addie’s age, sucking down a smoothie and texting nonstop. “Nanny?”

She nodded, chin quivering.

A tiny tweak wouldn’t matter, considering how unstable this world was. It was like a symphony—a single wrong note in a perfect performance could ruin the whole thing. But if the song was already riddled with mistakes, one more wouldn’t make a difference.

“No problem.”

Had I known I’d be climbing park benches in an attempt to rescue wayward balloons, I would have dressed differently that morning. Still, I dropped the backpack and climbed up, hoping a sudden breeze off the pond wouldn’t cause my skirt to pull a Marilyn Monroe.

“Almost there,” I said, wishing I were taller. Even atop a park bench in my motorcycle boots, I could not reach the ribbon. The kid eyed me dubiously. “Back of the bench should do it.”

I put one foot on the back of the bench, wobbling in my heavy boots, the string dangling inches away.

So much for a quick fix.

“Need a hand?” came a new voice.

Startled, I lost my balance. Someone grabbed me, one hand on my leg, the other at my waist. I looked at the fingers curving around my thigh—a guy’s hand, wide and strong, slightly calloused, with a leather cuff around the wrist—as dissonance roared through me, twice as loud as before. My knees buckled.

I knew him. A version of him anyway. I’d spent a lot of time studying those hands when I should have been focused on math or history or Bach. They belonged to Simon Lane. And Simon Lane, even back home, belonged to an entirely different world than I did.

He guided me down until I was standing on the seat, balance restored, dignity shaky. He let go, but the noise remained. He was the break by the duck pond. I focused on his sweatshirt, the faded blue logo of Washington’s basketball team, and willed the discord away.

He glanced at the kid. “Balloon got stuck?”

Her lower lip trembled. “This girl isn’t big enough.”

It was tempting to point out, standing atop the bench, that I was currently taller than Simon. But he was standing closer than he ever had at school, and his dark brown hair was a good two inches longer and shaggier than I was used to, and I got distracted. He knew it too, judging from the flash of amusement in his eyes.

“I can do it myself,” I said.

“She’s stubborn,” he told the girl, as if he was confiding in her. “If she’d lean on me, we’d have your balloon down by now.”

“You lean,” she ordered.

“Charming,” I said.

He nodded. “So I’m told.”

Some things—eye color, gravity, mountain ranges—were constant no matter how far you Walked. And Simon’s reputation as the guy all the girls wanted, even though they knew better, was apparently one of them.

I shook my head to clear the ringing.

“Fine. But don’t drop me.” I braced one hand on his shoulder and climbed up, both feet perched on the narrow back of the bench, feeling myself sway. His hands closed over my waist and I stretched, catching the string of the balloon, tugging until it came free of the branches. “Got it.”

“Jump,” he said, and I did. His thumbs brushed against my rib cage, lingering when they didn’t need to. This close, his eyes were a darker blue than I’d realized, more thickly lashed, and there was a tiny scar at the corner of his mouth I’d never seen before. Simon Lane, I thought dizzily, and pulled away.

I tied the balloon around the girl’s wrist, and she ran off without another word.

“You’re welcome,” I called after her.

“No good deed goes unpunished,” he said, grinning at me. “I’m Simon, by the way. You look familiar.”

“Del,” I said. “I go to Washington. With you.”

He squinted, trying to place me. It wasn’t his fault. Walkers didn’t have Echoes, the way regular people did. But we left an impression through the worlds, like a daydream. When I was in class with his Original, this Echo would see my impression hovering in his peripheral vision. If he tried to look at me directly, the image would fade away, and he’d forget about me.

Which was not so different from the Key World, now that I thought about it.

“Aren’t you supposed to be in class?” I asked.

He ducked his head for a moment, then looked up with a mischievous smile. Trouble, I thought. Way more than his Original, which was saying something. “Aren’t you?”

A voice from behind me, bossy and superior, said, “You have got to be kidding me.”

Addie.

Simon didn’t hear her, of course. Unlike me, Addie would have been careful to avoid touching any Echoes. Casually I looked over my shoulder. My sister stood ten feet away, hands on hips, foot tapping, eyebrows drawn together in disapproval.

“You cut class again?” she said.

“It’s only school,” I replied, keeping my eyes on Simon, answering both questions at once. “Most useless part of my day.”

I didn’t mention that I found my classmates equally so. They’d probably say the same about me.

Suddenly a soaking wet chocolate Lab raced past us, Frisbee clamped in his teeth, a red bandana around his neck. He circled Addie twice and dropped the orange plastic disc at my feet. He let out a thunderous bark and panted up at me as if looking for approval.

“Iggy,” Simon said warningly at the same time I said, “Good puppy.”

Which was all the encouragement Iggy needed to shake himself off, spraying pond water all over me.

“No!” groaned Simon. “Bad dog!”

I brushed at my clothes as Iggy romped around. “Serves you right,” Addie said, snickering. “You know Mom and Dad don’t like you Walking alone.”

Iggy woofed in her direction and put his paw out for me to shake. Gingerly I took it. Monty said animals liked Walkers because they could hear the difference in our frequencies, and we sounded good. Whatever the reason, the dog was all lolling tongue and blissful unrepentance, even when Simon grabbed his collar.

“Leave her alone, Ig.” The dog ignored him. “Sorry. I think he likes you.”

“Animals do,” I said, pulling at my drenched sweater.

“He’s got good taste.”

Addie tapped her watch, her face drawn. The noise was already getting to her. Iggy must have heard it too, pressing damply against my leg and whining.

“Chill, boy,” Simon said, scratching the dog’s ears. “Let me make this up to you? There’s a kick-ass band playing at Grundy’s tonight, and we just got new IDs. You should come with.”

“Absolutely not. Tell him no,” Addie said.

The real Simon would never go to a bar during basketball season. He had too much to lose. I must have frowned, because his eyebrows lifted, dark lines over dark blue eyes. “Okay, not Grundy’s. What about the Depot?”

In the Key World the Depot was a coffee shop on the south side of town, in the old train station. After a huge crash decades ago, the city built a new station on the north side, and the Depot became a landmark and a place for locals to get lattes.

Walkers believed every accident came from a choice. Nearly forty people had died that morning; another hundred were injured, simply because the engineer picked the wrong time to throw the brake. Countless worlds had sprung up in the aftermath, a lesson in the way a single decision could transform the fabric of the multiverse.

I wondered what choices had shaped this version of Simon, who cut class and used a fake ID. Despite his dissonance, I was tempted to find out. He was definitely the break, and it was just my luck that the one time he noticed me, there was something fundamentally wrong with him.

Iggy bumped my legs, and I fell heavily into Simon again. His arms came around me, and for an instant I let mine circle him. Then I took a quick, unsteady step back. “I’ll think about it.”

Now it was his turn to frown. Most girls would have been falling all over him for that kind of invitation, but I wasn’t most girls.

“Playtime’s over,” Addie said, her expression like a storm front. “Wrap this up.”

I gave Iggy one last pat. “See you around.”

“Count on it,” he said, scooping up the Frisbee and tossing it toward the pond. Iggy raced away, Simon followed, and I turned, awaiting the wrath of Addie.

“We’re not here to troll for guys, Del.”

“You’re not, anyway. I’m sure we could find you someone.” I pointed to a girl biking on the other side of the pond. “She’s cute.”

Playing matchmaker for Addie wasn’t a bad idea. Not that the outdoorsy type was right for her. She needed someone as effortlessly polished as herself. But if she had a girlfriend, maybe she’d be too busy to notice my mistakes.

Her green eyes took on a warning gleam. “Leave it alone, Del. Him too.”

I shrugged. “He’s a break. I was getting a reading for my homework.”

“Some reading,” she replied.

“How long have you been spying on me?” I asked, trying to draw her attention away from Simon.

“Long enough to see you get the balloon down. There was nothing wrong with that kid. You should have left her alone.” She crossed her arms, her face taking on the pinched, fussy look that made her look older, and not in a good way. “We have rules for a reason, Del.”

I studied my nail polish, plum colored and starting to chip.

“She was miserable.”

“So? She’s an Echo. It doesn’t matter.”

It matters to me, I wanted to say. But Addie was right. Echoes weren’t real people, only copies of Originals, no matter how alive they seemed. Still, her response, practical and dismissive, nettled me.

“Whatever.” I glanced over at Simon, roughhousing with Iggy. The discord surrounding them scraped along my nerves, growing louder the longer I watched. “Why are you here?”

“Dad asked me to help you with your homework. I left you three different messages.”

“Didn’t get them,” I said airily, pulling Simon’s wallet out of my pocket. I held up the out-of-state license that claimed he was twenty-four. “This is a terrible ID. They’d totally bust him.”

“You picked his pocket? Did Monty teach you?”

“Who else?” She frowned as I continued. “Simon’s Original is the star basketball player at my school. He’d never try to sneak into a bar. What’s the harm in keeping this one out of jail too?”

“It’s pointless,” she said, swiping at a wisp of strawberry blond hair that dared escape the neat twist at the nape of her neck. I never understood how she was able to get her hair to behave. Mine was a perpetual mess—reddish brown, unruly as tree bark, black at the ends like they’d been dipped in a pot of india ink. “He’s not even real.”

Simon’s palm on my bare leg had felt pretty damn real, but I kept that tidbit to myself.

I couldn’t say why, exactly, I’d nicked his wallet. Because it was fun. Because I wanted to test myself. Because while this Simon flirted, the one back home barely noticed me. Because even if he was only an Echo, I’d hate for him to end up in juvie. Because Addie couldn’t. A million reasons, but mostly . . . because I could.

I shook my head and slipped the wallet back into my pocket. “I hope he didn’t pay a lot for this. It’s awful.”

“Leave it here.” Her tone and temper were both growing short, but so were mine. “You know it’s dangerous to bring it back.”

“It’s not radioactive. It won’t hurt anything.” According to the Consort, bringing Echo objects to the Key World was like introducing bubonic plague, but they’d never explained why. It made sense for big things, like pets. Clear violation of the rules to bring Iggy back, since the real Iggy was already frolicking about somewhere. But an object as small as Simon’s wallet wouldn’t affect my world, the same way a single grain of sand wouldn’t hold back the tide.

Even so, it was easier to let Addie think she’d won, especially with a migraine brewing. I tossed the ID in the trash and the wallet on a nearby table, where he’d spot it on his way out. “Happy now?”

“Not really,” she said. “Let’s get started on your homework. The first step is to locate the vibrato fractums.”

“Already did. Simon’s one. Jogger’s two.” I jerked a thumb toward the trail where a stout, balding man was running. “Minivan’s three, but it pulled out while I was talking to Simon. Swing set makes four. Did I miss anything?”

I hadn’t, but it was fun to make her admit it.

She scowled. “Since you’ve got it figured out, go get your readings.”

“I already checked Simon,” I said, and flashed my phone. I hadn’t just picked his pocket—I’d recorded his frequency so I could determine exactly how bad the break was. “I can skip the others.”

“Three breaks, three readings,” she said firmly.

The thing about Walking is you’re always playing catch-up. It’s not time travel. You can’t go back and prevent a problem. Once a decision is made, a branch—the choice you didn’t take, an alternate pathway, an alternate world—is created. Most of the time, it’s no big deal. The alternate world, populated by Echoes, goes its own way. It creates Echoes of its own and never interferes with the Key World again.

Every once in a while, for reasons unknown, something goes wrong. There’s a snag in the fabric of reality, a frequency that’s grown too strong or too unstable. Left alone, it will spread, destabilizing the Key World and weakening the other branches of the multiverse. And that’s where Walkers come in—crossing through pivots, cutting off one reality to preserve the rest. Cleaving.

Breaks are the first sign of a problem, but they aren’t necessarily fatal. Like infections, some are more serious than others, so we have to determine which ones can be left under observation and which require cleaving. I didn’t doubt this world would end up cleaved—it was sounding worse by the minute—but Addie would never let me bail early.

I’d heard the jogger’s pitch warbling across the park, but the assignment required I get a direct reading to be sure. I started toward him as he came around the curve, checking his pulse, his face red and his shirt sweat-soaked. I shuddered.

I picked up the pace as he approached, his signature growing louder. Get away clean, Monty always said, and I hustled the last few steps, phone clutched in my hand.

Our paths intersected, my shoulder brushing against his arm. He stumbled onto the grass, yelped, and swore.

“Oops,” I said, and kept going. He threw up his hands and continued running. The touch had been brief, but long enough to turn my screen cherry red. I headed back to Addie. “That was gross.”

She fixed me with an expectant look. “Well?”

“Yes, obviously.” I showed her my phone. “I didn’t need a direct read to know he’s a bad break.”

“Augmented break,” she corrected, tugging at the hem of her tweed blazer. “He’s not good or bad; it’s a question of how far his individual frequency has degraded.”

“Whatever. Can we go now? This place sounds awful, and I have plans.” A sharp ping, like a violin string breaking, split the air. The wobble in the frequency sped up.

“A date with Eliot is not a sufficient reason to blow off training.” She rubbed her temples as she spoke. “Check the swing set.”

“It’s not a date,” I ground out. “It’s Eliot.”

Everything is possible, for a Walker. The multiverse is infinite, like an ancient tree with branches in every direction, each branch sending out countless shoots, each shoot sprouting an endless number of worlds. Walk far enough, carefully enough, and you could find whatever world you wanted. But you would never find a world where Eliot Mitchell and I were a couple. It was hard to feel romantic about someone you’d gone through potty training with.

I stomped across the playground to the swings and gripped the chain with one hand.

Discord knifed through me, and I let go as if scalded. Immediately the noise receded. I bent over, hands on knees, waiting for the nausea to pass before rejoining Addie.

“Done. Bet you they cleave this place by lunch tomorrow,” I said.

“The Consort’s not going to cleave a world because a fifth-year Walker said so,” she scoffed. “On the other hand, if I said so . . . I bet they’d let me help.”

Naturally they’d listen to her over me. “I found it.”

“You stole a wallet and let an Echo get grabby. You will not be helping.” She set off toward the pivot we’d come through. If I squinted, I could see the roadside marker flickering in and out of view, a sign this world was rapidly destabilizing.

I chased after her. “That’s not fair. I should at least get to try it.”

A thrill ran through me as I spoke, dark and compelling. My fingers twitched, sliding through the atmosphere, through time and space and perception until they touched the fabric of this world, the threads raucous and trembling. Like a key in a lock I hadn’t known was there, the sensation called up something more instinctive than memory, a sudden yearning to fix the snarled, too-tight lines straining against my skin. I hummed a half-forgotten song, only to be cut off by Addie.

“You. Aren’t. Licensed.” She took my arm, looking frazzled. “We go home. We tell Dad. We let the Consort handle it.”

“Why not save them the trouble?”

“Like you’d even know how.”

Over her shoulder I saw Simon lift a hand to wave at me. I smiled back, then caught myself. Not real. The Original Simon wouldn’t wave at me. He wouldn’t notice me. He definitely wouldn’t invite me out to hear a band or grab coffee or anything else. He wouldn’t have made me feel this uncomfortable regret. Not real—but very dangerous.

“It’s not hard,” I said, the heart of the world vibrating under my fingers, as reckless and chaotic as my own. “All you have to do is start.”

CHAPTER FOUR

When interacting with Echoes, do not let emotions cloud your judgment or divert you from your duty.

—Chapter Three, “Echo Properties and Protocols,”

Principles and Practices of Cleaving, Year Five

IT SHOULDN’T BE so easy to end a world.

When you think about it, unraveling the fabric of reality should require more effort than clipping your nails. As it turns out, all you need to do is find the right thread and yank.

Or hold on to the thread while your sister yanks you.

The strings slid away with such force I thought they’d slice my fingertips, the remaining fabric slack and gauzy. The ground at our feet warped like a Salvador Dalí painting, nearby trees going liquid and limp, the sky a smear of blue and white.

“What did you do?” Addie looked around wildly.

“It wasn’t my fault! You grabbed me!” A line of silver shot from the playground to the pond, which turned gray and began to fade.

“You shouldn’t have been messing around,” she snapped, pulling me toward solid ground.

“They were going to cleave it anyway,” I said. According to the Consort, cleavings were complicated procedures that required tools, and training, and time.

I’d done it completely by accident.

My stomach churned as I watched the ducks bobbing along the increasingly dim surface. They flickered, turning grainy black-and-white like an old movie, and then a blob of static, and they were gone.

White noise, like listening to a seashell, filled the air.

Simon threw the Frisbee and Iggy leaped, the color leaching out of the bandana around his neck. My chest squeezed painfully at the sight. I’d expected something . . . cleaner. A quick winking out of existence, like stars at sunrise. “I didn’t mean to.”

“Like that matters? We have to go.” She started toward the portal but stopped when she saw I wasn’t moving.

One by one, the cars in the parking lot guttered like candle flames. Even the ones with people inside them. “I did this,” I said hollowly. “I should watch.”

Addie’s voice was unexpectedly sympathetic, despite the note of panic creeping in. “Del, they’re not alive. They were never alive, just Echoes.”

“They don’t know that.”

“No, but we do. It’s cleaving too fast,” she said. “It’s supposed to start at the breaks and spread out from there. This is . . . random.”

She was right. The whole point of our training was to manage cleaving in an orderly way. Cleavers cut away the damaged branch, then rewove the strings, ensuring the healthy world stayed strong. The Echo was left to unravel at its own pace, triggering a domino effect. The worlds that sprang from the cleaved Echo would unravel as the effects spread. It was like pruning a shrub: Cut the base of a branch, and all the twigs and leaves attached would fall away too. The effects would take time, but cleavings were irreversible.

The chaos before us shouldn’t have happened for days, but already the wooded area beyond the paths had turned to a misty gray wall, the unraveling flowing across the field. The roaring in my ears increased with every Echo that disappeared. I turned, looking for the rift we’d come through.

“Addie?”

The grass around our pivot was silvery with hoarfrost.

“Come on!” She sprinted, graceful even when she was running for her life. I followed as best I could in my clunky boots and overloaded backpack. The asphalt was starting to soften and the curve ahead was fading. I could see where the edges of the world didn’t quite align, and hear the Key World’s frequency drifting through like a beacon.

Inches away from the pivot, the signpost for the park dissolved into a lumpy puddle. There was no way we’d reach it in time.

“Wait!” I caught the hem of her jacket. She ignored me, and I yanked harder. “We’ll never make it through—we’ll be caught in the cleaving.”

She whirled, eyes bright with fear. “We’re caught unless we get out of here, you moron!”

“Look,” I said. The signpost disappeared. An instant later, the pivot was gone too, replaced with the same formless gray overtaking the park.

Addie made a sound like a drowning kitten and went limp. “We’re stuck.”

The silver-coated ground crept toward us like fog. I tugged at her. “Back this way. The park.” For once, she didn’t argue. “There has to be an emergency plan.”

“Yeah. Don’t cleave a world while you’re standing in the middle of it!”

We reached the playground, where the disintegration was already setting in. The benches bowed toward the ground, the moms and nannies oblivious. The kids climbed on the jungle gym, unconcerned by the bars warping beneath their hands.

“No pivot points,” Addie said. “That’s the only way in or out.”

She was right. The ooze had overtaken the far end of the playground and the parking lot, where the strongest concentration of pivots was. It was impossible to cross. Iggy and Simon had been replaced by a sea of grayish light; so had the swingset and the spot where I’d bumped into the jogger. The Echoes never noticed. They’d fade before they realized what was happening, reabsorbed into the fabric of the universe.

We wouldn’t be reabsorbed. We’d be dead.

Addie dropped onto the bench and started to cry. I tried not to throw up. A few feet away the little girl with the balloon twirled, the balloon’s color bleeding away.

The balloon.

The balloon should have been tangled in the tree overhead.

I’d fixed it, and the kid had gone back to playing, instead of crying at the base of the tree.

And she was still here. Only . . . not for much longer.

“Move!” I hauled Addie up.

“It’s too small, Del. We’ll never get through.”

“You have a better option? Move your ass, or we’re dead!” I skidded to a halt inches from the girl. I listened as hard as I could for a frequency—any frequency—not obscured by the white noise of the cleaving.

“Hurry,” Addie said.

“Shut up!”

The balloon flickered as I heard one—E minor, haunting and sweet. Light filtered through the pivot, pale as dust and barely visible. I lunged for it, clutching my sister’s hand.

The last thing I saw was the little girl disappearing in a burst of static.

CHAPTER FIVE

The term “accident” is a misnomer. Every consequence, no matter how unexpected, is rooted in a choice.

—Chapter Ten, “Ethics and Governance,”

Principles and Practices of Cleaving, Year Five

I LANDED HARD. My palms and knees stung from the impact, and my ears rang in the sudden silence. Less than a foot away, the edges of the portal fluttered like the wings of a monarch and sealed themselves. Slowly, I sat up and brushed wood chips from my hair.

Addie lay nearby, flat on her back, panting and staring at the sky. The blue, blue sky. Azure. Lapis. Cornflower. Glorious, rich, head-spinning color. After the relentless gray of the world we’d escaped, I was practically drunk on it. I hauled myself up, using the jungle gym to keep my balance.

The scene before me was identical to the cleaved world. Joggers and kids and nannies. Ducks bobbing on the pond. Simon and his friend playing Frisbee with Iggy. My throat tightened and my breath eased simultaneously. Everything was exactly as it had been.

Almost. The little girl sat next to her nanny, head bent, shoulders shaking. I looked up and saw the balloon, caught in the highest branches of the tree. Soon the wind would carry it away.

I thrust my hands in my pockets and found my star, crumpled and half-finished. Smoothing it out, I folded the rest from memory, the movements familiar and reassuring.

Addie stood, her face white and set.

“Not bad, right?” I tried to smile, but it felt as wobbly as my legs.

“No, Del. That was bad. Very, very bad.” She swiped a finger underneath each eye, erasing the tracks of mascara. “We have to keep moving.”

“We’re safe.”

She shook her head and studied the playground. “When that world finishes cleaving, this one will start. It’s a domino effect, and you knocked over the first one.”

My stomach twisted, and I nearly dropped to my knees again. The Key World was safe, but every Echo originating in Park World would unravel and fade. Because of me. “What about the people?”

“Del. Focus. We have to find a pivot we can use to get home. Where’s our best shot?”

She must have been seriously rattled to ask me for advice, instead of ordering me around. It was almost funny. Almost, the way that this world was almost the same as the one we’d fled. “Almost,” as it turned out, meant “not at all.”

A sour taste flooded my mouth. “Parking lot,” I said. “There’s a ton of decisions in a parking lot.”

“Then let’s go. And don’t touch anything.” I glanced over my shoulder at the little girl, still crying.

“Thanks, kid,” I murmured, and followed Addie toward the rows of cars and pivots. The instant before I crossed over, I tossed the paper star toward the signpost. Pointless, considering this world would soon vanish, but it was habit.

A breadcrumb, just like Monty had taught me.

For someone who spent so much time talking up how she was the mature one in the family, Addie wasted no time reverting to childhood when we arrived home.

“I’m telling Mom,” she said, slamming the car door extra hard and marching up the driveway.

I chased after her. “You’re tattling on me? Seriously? Are we five now?”

“Five-year-olds have better impulse control,” she hissed. “We could have been killed. Do you think the Consort won’t notice? You cleaved a world.”

“You grabbed me,” I said, fighting back the fear that enveloped me. “I didn’t mean to do it.”

“It doesn’t matter what you meant. It’s what you did. And don’t try to blame me—you shouldn’t have been touching the strings in the first place. This is completely on you, Del.” She stalked inside.

I stood in the driveway, shivering as a chill worked its way under my sweater. Our kitchen windows glowed warm and yellow, the peeling paint less visible in the dusk. It looked homey. Safe. Cheerful. But I knew exactly what kind of welcome awaited me when I crossed the threshold, and it was none of those things.

The barberry bushes bordering the yard rustled, and a moment later Monty popped out, his cardigan catching on the thorns. He swatted at them, not noticing when his hands came away scratched.

“You’re back?” he asked, his voice thin and reedy like an oboe. Monty had been a big man once, but he’d diminished over the years. Most Walkers developed frequency poisoning as they aged, but his was especially severe. Too much time spent in bad frequencies had left his shoulders bent and his gait slower. He lost time, forgetting my grandmother was gone. Worst of all, his hearing was ruined. Without hearing, a Walker had to rely on touch to navigate through the multiverse. Difficult and dangerous, but it didn’t stop him.

“Hey, Grandpa.” I took him by the elbow. “How long have you been out here?”

“I was going out. Where was I going?” He patted his pockets, pulled out a cheap little spiral notebook and a pencil stub. “I wrote it down. I drew a map.”

Walker maps didn’t look anything like the jumble of lines and musical notes he was peering at. He’d end up lost. Real maps showed only the major, stable branches of an Echo, their important pivots color coded to show strength and stability. Computers had made them easier to maintain—the old bound versions, drawn on onionskin paper, were inches thick and instantly out-dated. Even with technology and experience on our side, tracing a path through the multiverse was no more accurate than charting wind currents.

“You’re not supposed to Walk by yourself,” I said, taking the notebook. Then again, neither was I.

A cagey light entered his eyes. “We can go together.”

“I—” The screen door flew open and my mother appeared, anger visible in the rigid lines of her posture. Addie stood behind her like a self-righteous shadow. “Mom—”

“Not a word, Delancey. Not. A. Word.” She pointed to the kitchen table, and I slunk past her to my usual chair. Monty followed me inside.

“Foster!” she called into the twilight. From his office in the garage, my dad shouted back something unintelligible, and then hustled inside. Nobody messed around when my mom used that tone.

Monty patted my arm. “She’s in a temper, isn’t she? Been snappish all day.”

“Do not move from that spot,” Mom said, her glare nailing me to my seat. Addie smirked as they filed into Mom’s office and shut the door.

“You’ve been out a long time.” Monty drew two glass bottles out of the fridge. “Root beer?”

“Not thirsty,” I mumbled as he pried off their tops.

He brought both bottles over and drained half of his. I rolled mine between my hands, listening to the faint hiss and snap of the carbonation.

“I screwed up,” I said. “Big.”

He belched gently, and I wrinkled my nose. “Nothing’s done that can’t be un-, Delancey.”

It’s what he’d always said, when I was a kid and we’d gone Walking together. A song he’d invented, special for me.

Nothing’s done that can’t be un-,

Nothing’s lost that can’t be found,

Make a choice and make a world,

Find another way around.

It had cheered me whenever our Walks had gone awry, and with Monty, they usually did. But I’d figured out by now that plenty of things—and people—stayed lost forever.

People like my grandmother. She had been a medic—the Walker equivalent of a doctor—charged with keeping Cleavers like my grandfather and my father healthy during their trips through the multiverse. A few months before I was born, she’d gone out on a Walk and never returned.

My parents and Addie had been living in New York at the time; Monty and Rose were here, in this house. According to my mom, the Consort’s teams had searched for weeks, but she’d vanished completely. Their official verdict was that Rose had been caught on the wrong side of a cleaving, like we’d been today.

Monty wouldn’t accept it. They were meant to be together, he insisted—Montrose and Rosemont, two halves of a whole. He’d wandered the multiverse alone, looking for her, until the Consort had stepped in and issued a second verdict: Either my parents come back to take care of Monty, or they’d send him to a home. So, a month after I was born, we returned permanently.

It was Walker tradition to name a kid after big pivots in their parents’ hometown, and few pivots were bigger than train stops, where decisions accrued on a regular basis, day after day. Everyone else in my family was named for Chicago, but I’d been named for New York, a reminder of what could have been. My grandmother’s disappearance had given me my name and an entirely different life.

When someone vanishes, it leaves behind a scar. Some heal better than others. My grandmother had unwittingly left her mark on our whole family. My mom saw the world as a collection of messes to be contained. Addie was so desperate to please her, she’d taken that need for order and translated it as a need for perfection. My dad tried to keep everyone happy, ever the peacemaker. The only path left to me was the one marked trouble.

Even now Monty didn’t believe my grandmother was really gone. He slipped away whenever he could to continue the search. But instead of finding Rose, he’d lost his mind.

His song had failed us both, but I didn’t tell him so.

“Now,” he said, leaning back in his chair and lacing his hands over his stomach. “What’s this about?”

“I cleaved an Echo,” I said. The words felt leaden as I spoke them, and Monty’s head snapped back as if he’d taken a punch. I hurried to explain.

“Not on purpose. I touched the strings for a second and it sort of . . . happened. Everything fell apart crazy fast. I’ve never been inside a cleaving. I didn’t know . . .” My throat clogged up. “There was a guy from school—an Echo of a guy from school. Simon Lane. One minute I was talking to him and the next he was gone.” Monty’s eyebrows lifted, his watery blue gaze turning sharp. “I know they’re not real, but . . . that’s not how it felt. It felt awful.”

He nodded. “As it should.”

“We barely got out in time, Grandpa. I thought unravelings took days.”

He looked like I’d given him a prize instead of a problem. “How’d you manage to escape?”

When I explained about the balloon, he chuckled. “Clever girl.”

I didn’t feel clever. I felt sick. “I didn’t mean to. It was an accident.”

“There are no accidents,” said my mother from the doorway. My father’s hand rested on her shoulders, a unified front.

I turned to plead my case. “I only wanted to know what the threads felt like. I’d never been anywhere so out of tune. Then Addie yanked me away, and they split. That’s it.”

“That’s it?” Mom’s voice was like a lash. My father stepped between us.

“You two must be starving. We’ll talk after dinner.”

I barely touched my food. Monty smacked his lips, slathering butter and jam on a biscuit. How could he be so cheerful after what I’d told him? My parents were ominously quiet, while Addie spooned up delicate bites of lentil soup with a satisfied air. Whatever punishment they’d decided on, she was happy. It must be bad.

Finally my dad pushed his bowl away. “Your actions today were reckless. And dangerous. Do you know what could have happened to you and your sister?”

I stared at the brown ooze congealing in front of me.

“You could have been killed. And we’d never have known. This is exactly why we don’t like you going out by yourself. Did you even think about us? What it would have done to your mother, living through that again?” Dad asked.

“This isn’t about me,” said my mom. She folded her napkin precisely and set it on the table. “This is about you, and your behavior, and your constant need to flout every rule that has been laid out for your own protection and the protection of the Key World.”

“I’m sorry.” I slid lower in my chair. “I didn’t mean for it to happen.”

“You never do,” my mom said. “You rush in and trust that your gifts will be enough to get you out of any mess you create.”

I poked at my bowl. I’d screwed up, but I’d also saved us. That should count for something, shouldn’t it?

“It was a neat trick,” Monty said. “Getting out of there. You should give her some credit.”

Gratitude rushed through me. Monty understood.

“She wouldn’t have needed a trick if she’d followed the rules,” Mom replied. “Addie made it through five years of training and we never once saw this kind of behavior.”

No, of course not. I’d figured out a long time ago that I couldn’t beat Addie at her own game, so I stopped trying.

My father added, “Cleaving can’t be handled by one person. The protocol mandates three Cleavers to manage it safely.”

“Hogwash,” said Monty. “They send three Cleavers so no one knows who cut the last string. Keeps ’em from feeling too guilty.”

“Why would someone feel guilty?” asked Addie. “They’re only Echoes.”

Monty shook his head in disgust.

“A faulty cleaving causes more harm than good,” my father said. “It leaves the Key World weak.”

There was no greater crime than damaging the Key World. My voice sounded very small when I said, “We can fix it, right? We don’t have to report it?”

I thought about the stories I’d heard, Walkers stripped of their licenses, forced to live like ordinary people, never again venturing outside the Key World. Walkers who vanished altogether, sent to an oubliette.

Oubliettes were prisons, hidden behind rumor and speculation. The story was, to contain the worst of our criminals, the Consort had played with the fabric of the multiverse. They’d created worlds no bigger than a jail cell, severing them from the Key World and Echoes except for a single thread. A world with all possibilities eliminated, impossible to escape. No one had ever come back from an oubliette, so no one knew the truth.

But I’d been reckless, not malicious. I wasn’t even seventeen—surely the Consort wouldn’t want to sentence a teenage girl to life in a prison world. Even so, I wasn’t eager to test the theory. “Dad, please. We can’t tell the Consort.”

Regret tempered the firmness in his voice. “We already have.”

“You’re supposed to be on my side!” I’d expected that kind of betrayal from Addie. But not my parents. Not my dad.

“We are. A cleaving that big can’t be covered up, and it’s better to admit what you’ve done. Take responsibility for your actions,” he said.

“It was an accident!”

“The Consort has rules, Del. If you want to be a Walker, you have to prove you can follow them.” My mom’s frown made it clear she wasn’t willing to bend the rules for me. Addie’s penchant for the straight and narrow was as genetic as our ability to Walk.

I wanted to remind her it wasn’t rules that had saved our lives today, but the breaking of them. And that I wasn’t going to be an Echo of my sister, no matter where we Walked. I didn’t say any of those things, though, because my mom would never truly hear them.

Monty had dozed off, crumbs scattered across his cardigan. Addie toyed with her necklace, pretending not to listen. My dad’s hand laced with my mom’s in a silent gesture of support.

I was on my own.

CHAPTER SIX

Counterpoint is the combination of two independent melodic lines into a single harmonious relationship.

—Chapter Five, “Composition,”

An Introduction to Music Theory

GO BACK TO the part about the balloon,” Eliot said the next morning.

“Really? I cleave a world, barely make it out alive, my parents narc on me to the Consort, and the freaking balloon is the part that interests you?” I threw my physics book into my locker and slammed the door. “My parents couldn’t even tell me what happens next. We have to wait for the Consort to decide. What if they put me in an oubliette?”

“They won’t,” he said. “There has to be an explanation for why the world cleaved so easily. And the only weird thing was the balloon, right? The rest of the Walk was by the book. So we’re missing something.” Behind his glasses, his brown eyes took on a familiar, faraway look. Deep in the supercomputer that was Eliot’s brain, he was sifting through everything I’d told him, searching for a clue, a pattern, a reason. “We’re definitely missing something.”

“Nothing important,” I said, thinking of Simon’s fingers curving around my thigh.

“Everything’s important, Del.”

I shifted my books from one arm to the other. Walkers kept their abilities secret from the rest of the world. I kept all sorts of things secret from my family. But Eliot and I had never kept secrets from each other. I’d explained Echo Simon and Iggy and the fake ID easily enough. But when it came to our encounter at the bench, I wasn’t ready to share.

Despite the crowded hallways, we reached the music classroom with time to spare. Eliot pulled at my sleeve to prevent me from going in. “If we can prove there was something wrong with the world, and that’s why it cleaved, they’ll have to go easier on you.”

“It’s the Consort. They can do whatever they want.”

“They can’t rewrite your DNA.”

He had a point. The Consort couldn’t take away my ability to Walk, but they could make it illegal. I’d be monitored for the rest of my life, unable to Walk without an accompanist. “What if they never grant me a license? I’d be stuck here.”

I’d be like an Original, only worse, because I’d know what I was missing.

“I’ll take you anywhere you want. All you have to do is ask,” Eliot said.

His eyes were oddly serious, despite the smile, and I had the distinct feeling that now I was the one missing something. Before I could ask, our teacher, Ms. Powell, appeared in the doorway.

“Am I interrupting, you two?” Smiling, she motioned us inside.

“Nope,” I mumbled.

If school was a wasteland, orchestra and music theory were my oasis—a break from the monotony of my day, a place where people spoke my native tongue. Ms. Powell was the only teacher who didn’t treat me like a delinquent.

Eliot and I slid into our seats at the back of the room. Simon sat at the desk in front of me, his dark hair starting to curl along the nape of his neck. As usual, it looked slightly unkempt, like he’d just rolled out of bed. Rumor had it that he’d rolled out of a lot of beds.

Park World Simon’s hair had been shaggier, falling past his collar, nearly hiding his eyes. The memory sent a stab of guilt through me. Simon must have felt me staring, because he twisted in his chair, flashed me a smile.

My own smile rose in answer—and disappeared as the girl sitting next to him noticed me too. Bree Carlson, star of the drama department, lead of nearly every musical and school play since the sixth grade. Pretty but not so gorgeous that the other girls hated her, popular but not so cutthroat that she had to watch her back, Bree was a chameleon; she acted whatever part would put her in the spotlight.

She and Simon had been together at the start of the year, but they’d split up about a month ago. The relationship had followed his typical pattern—a slow, easygoing shift from flirtation to coupledom to friends. Being dumped by Simon Lane was practically a badge of honor. I was surprised his exes didn’t have an official club, with a page in the yearbook.

Judging from the way she trailed her fingers over his shoulder, I could see she’d decided to reprise her role as Simon’s girlfriend. But in all the time I’d been watching him, he’d never gone out with the same girl twice. She had a better chance of nabbing a Broadway lead.

Which didn’t ease the sting when he turned back to her as if I wasn’t there.

“Since when do you smile at that guy?” Eliot grumbled.

I elbowed him. “Jealous much?”

Ms. Powell hit the lights and launched into her lecture on counterpoint, complete with slides. I tuned out Eliot’s sputtering and tried to focus. Even so, my thoughts kept drifting to Park World Simon versus real Simon. Bedhead wasn’t the only difference between the two. The leather cuff on his wrist was gone, replaced by a sporty, complicated-looking digital watch. This Simon had shadows under his eyes, the kind that took longer than a single late night to acquire. I wondered what—or who—had put them there. Eliot had always been better than me at pinpointing the changes between realities, but asking for his take on it would have meant admitting how close I’d gotten to Simon during the Great Balloon Rescue.

Forty minutes later the lights came back up, and Ms. Powell slapped her hands together with undisguised glee. She looked like a cross between a mad scientist and a 1950s housewife, wiry blond hair piled on her head and secured with pencils, a shirtdress printed with bluebirds, and a pair of orange patent-leather heels.

“So, your next project, to be done with a partner, is to develop and perform your own example of counterpoint, sixteen measures long. Fun, right?”

“This was supposed to be my blow-off class,” Bree hissed to Simon, who shrugged. Despite being my parents age, Ms. Powell was new this year and naive enough to believe everyone was here because they loved music as much as she did. It was kind of endearing.

Ms. Powell continued. “This time around I decided it would be good to shake things up.”

Nothing good had ever come from a teacher’s desire to shake things up, and I braced myself.

“Rather than pick your own partners for this composition, I’m going to assign them.” She chuckled at the groans that rose up. “You know what they say—familiarity breeds contempt.”

There was plenty of contempt in the room, but it was all aimed at her. I might have felt sorry for her, if I hadn’t felt like she was pitching her little speech directly to me. Walker training or school projects, Eliot and I were a team, and she was about to split us up. I slouched down as she yanked on the screen. It rolled up, displaying neat columns of names.

Eliot made a choking noise, but I couldn’t tell if it was because he was partnered with Bree—who didn’t look any more thrilled than he did—or because I was paired up with Simon.

“We can switch partners, can’t we?” Bree asked, tossing her hair back. “If both groups agree?”

“If I wanted you to pick your own partners, I would have said so from the beginning,” Ms. Powell replied, unfazed by Bree’s venomous look.

Bree huffed and flounced without leaving her seat, then bent over to whisper something to Simon.

“You okay?” Eliot murmured. “You look weird.”

“Thanks,” I said through gritted teeth. “I’m fine.”

He spun a mechanical pencil between his fingers, an over-under pattern I knew he’d spent hours practicing. “Watch him, okay? He’s . . .”

“I know what he is.” Trouble. My area of expertise. “Better than being stuck with Bree.”

“She’s not terrible,” Eliot said, and pushed his glasses back up his nose. “Not terrible to look at, anyway.”

It wasn’t jealousy, exactly, that zinged through me. More like annoyance that he’d fallen under her spell so quickly, like he was any other guy. Worry, too. I knew how much experience he had with girls, and none of it was enough for him to deal with Bree. She’d have him for a midmorning snack and forget about him by lunch.

“Longest sixteen measures of your life,” I said, and froze as Simon twisted around to face me again.

“Hey,” he said, friendly despite the tension swirling around the four of us.

“Hey,” I said, feeling stupid and obvious. I stared at the scar at the corner of his mouth, the one I’d seen in another world.

Ms. Powell spoke. “Now that you have your partners, take a few minutes to get acquainted, and we’ll—” The bell rang, off-key enough that Eliot and I both winced. “Never mind. We’ll pick this up tomorrow.”

“See you tomorrow, partner,” Simon said, and turned to gather up his books.

“Today,” I said, and he swiveled back, looking confused. “We have history together? Last period?”

He nodded slowly, but it was clear he’d never noticed. Heat rose in my cheeks.

“Can you believe Powell?” Bree said, tugging him toward the door. “This class is such a waste.” He didn’t give me a second glance. As usual.

I shoved everything into my backpack and followed Eliot into the hallway. “She actually split us up.”

Eliot looked up from his phone and blinked. “Huh? Yeah, it sucks. Why’d your mom send you and Addie to that Echo?”

“She didn’t. The assignment was to pick the Echo ourselves, remember? And it wasn’t supposed to be Addie. My dad bailed at the last minute.”

“But why did she approve it? I’ve been looking at the data you brought back, and those breaks were way outside acceptable stability parameters. She should have noticed when she ran the map.”

“The map was fine when she ran it.” My training Walks had to be analyzed by a licensed Walker before I could go out. Years ago that meant a navigator had to check each Echo in person. These days they ran the proposed route through a computer, and an algorithm would determine if it was safe to visit. My mom was one of the best navigators around; if she said a world was stable enough for a homework assignment, it was. “Echoes go bad all the time.”

“A branch that big should take weeks to degrade. Yours changed in hours.” He shook his head. “Maybe your mom screwed up. If the world was damaged before you arrived, you’re not to blame. She is.”

The Consort would be a lot tougher on a full-fledged Walker. She could lose her position—or worse. “My mom doesn’t make those kinds of mistakes.”

“Neither do I,” he said. “This wasn’t your fault, Del.”

I remembered the sensation of the strings, knotted and straining against my fingertips, and wondered if, for once, Eliot was wrong.

The day did not improve. “Delaney,” Bree called out with forced cheer on my way to ninth hour. I kept walking.

“Delaney.” She tapped my shoulder sharply. “I was calling you.”

“Delancey,” I said. “Not Delaney.”

Bree waved a hand. “Whatever. Can you believe Powell?”

I should have known she wasn’t going to let the assignment go. We weren’t friends. I didn’t have any Original friends, and if I did, she wouldn’t be one of them. I folded my arms and waited.

“We should be allowed to switch partners,” she said, oozing chumminess. “Don’t you think? It’s not fair that we have to depend on someone we don’t even know for a grade. What if we don’t get along? What if they’re a complete idiot?”

I bristled, but kept my tone syrupy. “Eliot won’t hold that against you. He’s very patient.”

Her mask slipped as my words registered. “You don’t have to be a bitch about it. Won’t you be happier sticking with you own kind?”

“My own kind?” I didn’t think she meant Walkers.

She simpered. “You know. Socially speaking. I’m only trying to help.”

“Sweet of you to worry. But Powell won’t let us switch.”

“She will if you ask. For some reason, she likes you.” She looked me over, the brightness in her voice ringing like steel. “Convince her to let us trade.”

Annoyance shifted to anger. “Why? So you can climb all over Simon? He was tired of you back in September, Bree. He won’t be interested in a rerun.” I turned on my heel and left her fuming in the hallway.

Bree and her friends viewed everyone as either a stepping stone or a target. I was the weird girl who was constantly skipping class and blowing off homework, so far on the fringes of the social scene I didn’t qualify as either. I wasn’t dazzled by her talent or taken in by her performances, but I’d never tried to outshine her. At most, I’d been an afterthought.

Now I was a threat.

“Del,” said Mrs. Gregory as I slid into my seat. “Good of you to join us. We missed you yesterday. As we so often do.”

“Not all of us,” said Bree, coming in behind me. Snickers crackled through the room.

“Family emergency,” I said.

“And yet the office has no record of either one of your parents calling to inform us of this . . . emergency. Which means, as you’re certainly aware by now, your absence is unexcused.”

I sighed. The Walks I took during school weren’t part of any assignment. They were my own secret ramblings, illegal but irresistible. I couldn’t stand being cooped up in a classroom, not when the multiverse beckoned to me from every pivot I passed, new frequencies calling to me like a siren song. The War of 1812 or quadratic equations couldn’t compete. Hence, my familiarity with the inside of the dean’s office.

Gathering up my books, I waved halfheartedly. “See you tomorrow.”

“Don’t leave yet.” She gave me a stack of papers and a thin smile. “Pass these out, if you will. You can see the dean after our pop quiz.”

Like one quiz would make a difference to my abysmal grade. Wordlessly I started circling the room. When I reached Bree’s desk, she took a paper and casually, deliberately, knocked the rest out of my hands.

“Sorry,” she said.

I bent to scoop up the papers, and she added, “At least he knows I exist.”

“Excuse me?” I reached for another quiz, and she planted her leopard-print ballet flat on top of it.

“Simon. Did you honestly think one stupid project would give you a shot with him? You could disappear tomorrow and he’d never notice. He doesn’t even know your name.”

I stood, papers crumpling in my fist. Mrs. Gregory called, “Del, the quizzes? We don’t have all day.”

Sotto voce, Bree murmured, “Watch yourself, freak.”

I forced my fingers to uncurl. She settled back, triumphant, her ponytail swishing as she surveyed the room. I looked at the sheaf of papers in my hand, the questions so foreign I might as well not bother.

So I didn’t.

“Del! What are you doing?” Mrs. Gregory called.

“Saving time,” I said, swinging my backpack over my shoulder. “I’ll tell the dean you said hello.”

CHAPTER SEVEN

Every Walker leaves an audible trail when moving through Echoes, as does any object brought from the Key World. Over time, the signal will weaken until it becomes untraceable, though inanimate objects hold signatures longer than people.

—Chapter Two, “Navigation,”

Principles and Practices of Cleaving, Year Five

WHEN I GOT home from school, disciplinary paperwork stuffed into the bottom of my backpack, my mom was sitting at the kitchen table. A glass jar of buttons stood at her elbow and one of Monty’s sweaters lay in her lap. “The school called.”

“I know.” I’d been sitting in the dean’s office when he dialed. “I’ll be more careful next time.”

“There’d better not be a next time,” she replied, and snipped a loose thread. “Have a seat.”

I dropped into my chair. “You heard from the Consort?”

“They want to see you tonight.” She tugged at the button and made a small, satisfied noise. “Daddy and I will take you in.”

The last thing I wanted was an hour-long lecture in the car. I glanced at the teapot, squat and fire-engine red, the same color as the little girl’s balloon. My throat tightened, but I said, “I’m going with Eliot.”

“He can ride with us. We need to be there.”

“You don’t need to. You’ve already turned me in, Mom. Isn’t that enough?”

“That’s not—” She broke off as Monty wandered in, clutching the sports section of the newspaper.

“I’m cold,” he complained.

“Perfect timing,” Mom replied with forced cheer, and helped him into the sweater. He must have given her a rough time today—the more difficult he was, the more upbeat she got, as if she could reverse his decline solely through willpower. “Honestly, Dad, I don’t know how you manage to lose so many buttons.”

Monty winked at me and put his finger to his lips. I stifled a laugh, despite my mood.

“Good as new, and here’s my best girl in the bargain.” He gave me a whiskery kiss on the cheek. “Have you been out Walking? Did you see Rose?”

“I was at school, Grandpa.”

“It’s late. She should be home by now,” he said, and swiped a handful of buttons from the jar. “We should look for her.”

“How about a snack?” Mom said. She packed up the sewing kit with exaggerated care, like the precise arrangement of threads and needles would somehow make everything else fall into place.

He paused, his hand on the doorknob. “A snack?”

“I’ll fix you something,” I said quickly. When Monty lost time, distraction was the only way to stop him from taking off. “How about granola? With honey on top?”

He scratched his chin, considering, and then sat as if he was doing us a favor. My mom exhaled. “I’m going to finish up some work. Del, we’re leaving in an hour.”

I didn’t answer.

“Have you been out Walking?” Monty asked again when she left. “Did you see Rose?”

“Nope. School, remember?” He did this a lot, asking the same questions over and over, as if the answer would change.

“You’re in trouble,” he said. “I heard them talking.”

“Yep.” I kept my tone even and my face hidden behind the pantry door. “I . . . made a mistake. When I was Walking with Addie.”

He made a harrumphing noise. “Nothing’s done . . .”

I was not in the mood for rhymes. Not with so much at stake. “I cleaved a world, Grandpa. It doesn’t get any more done.” I spoke more softly. “It was an accident. I know they don’t believe me, but it was.”

Monty didn’t say anything, and I dug through the shelves for the giant mason jar of granola. “You know what I don’t understand? If Echoes are such a threat, why am I in trouble for cleaving one?”

The air around me quivered. As quietly as I could, so as not to disturb the chord, I backed out of the pantry and turned my head toward the table.

“Damn it, Grandpa!”

Monty was gone, the pivot point he’d used trembling faintly. If I hurried, I might be able to catch him before my mom realized he’d wandered off. In a way, I admired how neatly he’d played us, but I doubted my parents would see it that way.

If they found out.

I’d need to be fast, not only to keep my mom from discovering I’d let Monty escape, but because his signature would only last a little while. I had to find him before the trail went cold.

Grabbing my backpack—even on a quick trip, I wanted my tools nearby—I followed him through the rift.

Monty had been tracing my grandmother’s path for so long, he was Walking between worlds at random, searching for a hint of the frequency that meant she’d been there. He’d never found one.

I was luckier. I let the cacophony of the pivot swallow me up, searching for the smooth, crystalline pitch of the Key World. Only a few minutes had passed, and Monty hadn’t gone far—his signal was loud and clear, nestled in an Echo with a frequency close to ours.

This Echo was old. Someone else had moved into this version of our house and rehabbed it, the empty kitchen gleaming and catalog worthy, with artful flower arrangements and perfectly staged clutter instead of the actual clutter that filled every surface of our house, despite my mom’s efforts. A neat line of monogrammed backpacks hung from hooks by the open back door.

I dashed outside and heard the next pivot point, whirring like crickets at dusk. When I crossed through, a giant spruce had replaced the crimson-leafed maple in my backyard. Nestled against the trunk was a bright yellow button, resonating at the Key World’s frequency.

Monty’s breadcrumb.

I got lost once, when I was five. My parents had been busy working, Addie was practicing piano, and I’d slipped outside on my own. I’d found an unfamiliar Echo of our backyard, with a full swing set—a slide and glider and monkey bars instead of the single rope swing my dad had made for Addie and me to share. I’d loved it, until I lost track of time. The pitch that had started out as intriguing transformed into overwhelming. I couldn’t find the pivot I’d come through, and I couldn’t hear any others.

That’s when Monty appeared, button in hand. He’d scooped me up in his arms and called me his best, most clever girl. A glow spread through me at his words. Even back then, I’d grown tired of hearing how smart my sister was. He’d given me the button, ringing with the sound of the Key World frequency, and promised that as long as I left a trail of breadcrumbs, he would always find me, and together we would find the way home.

These days I usually didn’t want to be found. But I left a trail of paper stars when I Walked anyway, both habit and reminder of the fun we’d had.

When I stepped through the next portal, he was waiting for me, leaning against a mailbox shaped like a giant fish.

“You scared me!”

“Nothing to be scared of,” he said, pulling a shiny silver button from his pocket. “I wanted to stretch my legs.”

“Mom’s going to kill me,” I said. “We have to go back.”

“It’s a beautiful afternoon, Delancey. Walk with me.”

He flipped the button to the ground and set off, singing under his breath. I could see the village water tower in the distance, the same view I’d grown up with, but we were standing in a development of Tudor-style townhomes, with steeply pitched roofs and wooden cutouts decorating the balconies, exactly where our once-stately Queen Anne should have been.

You learn pretty quickly not to mourn the changes in a world. It wasn’t a Walker’s place to decide which Echoes were better, only to decide which ones were threats to the Key World. Sadly, chintzy housing was not considered dangerous.

I chased after Monty, linking my arm with his.

“Grandpa, the Consort wants to see me. Tonight.”

“Bah. There’s time enough.” He stopped short. “Feel that?”

His mind might have been going, and his hearing was shot, but he retained the touch. I stretched out my hand, quieted my mind, and felt the quiver of a pivot point I would have missed on my own.

Again and again, the ground changed under our feet—from sidewalk to dirt road to cement to blacktop to grass—a sign we were making big jumps between worlds. In every one, he dropped another button and smiled slyly, like a kid who’d gotten away with something. We were far from the Key World now, wandering among Echoes of Echoes.

I loved how vast the multiverse felt on these Walks, hungered for the possibilities. Someday I’d travel not only in the Echoes of the world I knew, but all over the globe. If I could find this much variety when we’d covered only a few miles, what would it be like to explore Echoes of Rome, or India, or Antarctica?

My steps slowed. How many Echoes had I destroyed with my cleaving? How many possibilities had I unraveled?

“You’ve cleaved worlds before, haven’t you?” I asked Monty. “Back when you were a First Chair?”

“When I was young and foolish.” His tone softened. “It bothers you, what happened.”

“I keep thinking about them.” About those people, rippling away, as if they’d never existed in the first place. “Did it bother you?”

He studied the cracked sidewalk and finally said, “Still does. As it should.”

“They’re just Echoes,” I said. “That’s what everyone says.”

“Not everyone.” He brightened, our conversation forgotten. “You choose the next one.”

“I choose we go home.” I checked my watch—Eliot would be at my place soon. If I intercepted him, we could head out before my mom realized we’d left. We could cross directly from here to the Key World, but we’d still need to get from downtown to our house.

“We used to have such fun,” he wheedled. His chin had taken on a stubborn set. “One more.”

“One, and then we go home.” I surveyed the grungy Echo we’d stopped in. Every third storefront was boarded up; graffiti scrawled across the plywood; the gutter was littered with food wrappers and cigarette butts and pulpy shreds of newspaper. At home we would have been standing directly outside a juice bar.

He grinned crookedly. “Are you hungry?”

We watched as a woman in Snoopy-print scrubs hesitated at the intersection, then decided to wait for the WALK sign. A pivot sprang up.

An instant later a Ford sedan blew through the light.

I shuddered. On the other side of the pivot, had her newly formed Echo made it across?

Either way, her choice had given us an opening. Monty hummed a target pitch and motioned to the rift. “Go on. Nimble fingers.”

Another childhood song from our Walks, as ingrained in my mind as the ABCs.

Nimble fingers, open mind,

Hum a tune both deft and kind;

Nimble fingers, open mind,

Help to seek what you would find.

I reached inside, the right frequency snagging my attention like a radio signal breaking through static. Keeping a firm hold on Monty’s sleeve, I eased into the next Echo. When we were safely on the other side, I took a deep breath, tasting sugar in the air. Across the street was a bakery with a pink-striped awning and a window full of sweets.

“Doughnuts!” He rubbed his hands together. “Don’t tell your mother. She’ll say I spoiled my dinner.”

“Trust me, I won’t say a word. How did you find this place?”

“I ramble,” he said distantly, tugging on my sleeve. “Don’t suppose you’d like to buy an old man a treat?”

I knew he’d had a reason for bringing me here. The frequency was off-key, but not grating. We could stop for a few minutes. I handed him a crumpled five, hoping it matched this world’s currency. “One doughnut. And be fast, okay? I need to get home.”

He patted my arm. “We’re right on schedule.”

I trailed after him as he crossed the street. This version of downtown was miles better than the one we’d left. The sidewalks were clean, the storefronts filled, even if they weren’t quite as upscale as home—a hardware store instead of an art gallery, a pawn shop instead of an antique store, a pharmacy instead of a yoga studio. The street was lined with cars, and plenty of people chatted on the sidewalk. Monty made sure to brush against one as he entered the store, so he was now fully visible. Outside the bakery, a dog was tied to the armrest of a bench. A chocolate Lab. With a red bandana.

“Iggy?” I whispered. Echoes often overlapped, but seeing Iggy so soon after watching him unravel was as jarring as any frequency I’d encountered.

His answering barks shook the windows, and he leaped up, straining at the leash.

I blinked. Some animals’ hearing was so sensitive, they could recognize Walkers before we made contact. Iggy was obviously one of them.

“Good boy,” I crooned, inching forward with my hand extended. “What are you doing here?”

As if in answer, the bakery door opened and Simon strolled out, white paper bag in hand. A different Simon, I reminded myself, taking in the layers of flannel and denim and leather, the messy hair, the battered work boots. Not a basketball in sight.

“Settle down,” he said, untying the leash. The dog bolted, seventy-odd pounds of enthusiastic fur crashing into me. I rubbed his silky ears, staring at my third Simon in two days, trying to recall Park World’s frequency. This one was less grating—and much more stable. My stomach unclenched at the knowledge this Simon was safe. I didn’t think I could handle seeing him unravel again.

He grabbed Iggy’s collar, his hand brushing mine. The strength of his signal sent me reeling, and he met my eyes, interest sparking in his own. “You’re making me look bad, Ig.”

Not much made Simon look bad. Even his legion of exes sighed and talked about his eyes or his hands or his laugh. He wasn’t the type to stick, they said, but it was fun while it lasted.

I was not interested in fun.

“Iggy won’t bite, I promise,” Simon said, misinterpreting my frozen silence. I looked at his hand, wrapped around the leash. Instead of the leather cuff or digital watch, he wore what looked like a silver railroad spike hammered into a circle around his wrist. But his hands looked the same, strong and capable and slightly calloused. “Don’t I know you?”

My nerves kicked up, a swarm of butterflies spreading from my stomach through my body, a hundred thousand wings beating in unison.

“Del,” I said, my voice scratchy. “School, maybe?”

“Maybe,” he said. “Or maybe I need to get my eyes checked.”

“Oh?” I asked, checking the bakery. Through the window, I could see Monty peering at the pastry cases.

Simon’s voice dropped, warm and inviting. “Something must be wrong if I haven’t noticed you.”

I turned back. “Really? That’s the best you can do?”

At home I would have stuttered and stumbled. It was easier to deal with him here, when it wasn’t real and didn’t matter. His smile turned rueful and somehow even more charming. “Too obvious?”

“You’re not going to win any points for originality. What are you doing here?”

“It’s Thursday,” he said, holding up the white paper bag. “My night to make dinner. I always pick up cookies for my mom, to make up for the inevitable kitchen disaster.”

“You could learn to cook,” I pointed out.

“I don’t mind,” he said with a shrug. “Besides, if I hadn’t stopped by, I wouldn’t have run into you.”

There was an Echo where he hadn’t, and I was unreasonably, alarmingly happy to be in this world instead.

“There’s a band playing at Grundy’s tonight,” he said. “They’re supposed to be pretty good. Want to meet up?”

This invitation was as surprising as the first one. It wasn’t unusual for Echoes to mimic each other, if their branches were close enough. And just like in Park World, I had a million reasons to say no. But sometimes the best decisions are the ones made on instinct and impulse. Sometimes a choice isn’t a simple yes or no, but the truth made visible, strong enough to hold up a world.

I wasn’t sure I was ready for that kind of truth.

The bell over the bakery door jingled and Monty appeared, long john in one hand, coffee in the other, a cruller clamped between his teeth. “I have to go.”

Probably not the reaction Simon usually got when he asked a girl out. His forehead wrinkled. “Is that a yes?”

I bit my lip. “It’s a maybe. Bye, Iggy. Stay out of trouble.”

Grabbing Monty’s arm, I steered him back toward the pivot.

“Making friends?” Monty asked around his cruller. His gaze, sharper than usual, followed Simon and Iggy as they crossed the street and climbed into a battered black Jeep.

“Simon Lane. He’s a guy from school.” I checked my watch. Eliot would be arriving at my house soon.

“Simon,” Monty said. “Wasn’t he the boy—”

“From the cleaving,” I finished. “Yeah.”

He nodded, obviously pleased with himself for remembering. The walk back to the Key World was fast and easy. We turned onto our block as Eliot pulled up in his mom’s Subaru, parking in Addie’s usual spot. She was typically back from her apprenticeship by now—she would arrive home a few minutes before Eliot and I left for training, offer advice we hadn’t asked for, and then go inside to finish up her day’s paperwork.

“Where’s Addie?” I asked.

Monty licked a bit of frosting from his thumb. “Your mother said she was meeting with the Consort.”

“By herself?” That didn’t make sense. Mom had been adamant I not see the Consort alone. Why would Addie be any different?

“Seems so.”

If Addie could deal with the Consort by herself, I could too. “Can you get in by yourself? You won’t wander off?”

“Don’t worry about me,” he said, patting my hand. “Now go on, before your mother catches you.”

I kissed his cheek and ran for Eliot’s car as Monty ambled around the side of the house.

“Go!” I said, throwing my bag onto the seat and sliding inside.

“Hello to you, too. Is there a problem?” Eliot asked.

“Not unless my mom catches us. Drive, will you? I want to make the early train.”

“Seat belt,” he replied, shifting into reverse. “I feel like I’m driving a getaway car.”

“Then act like it.” As we pulled away, my mom stepped onto the front porch, hands on hips.

“Delancey!” The shout was faint, but I was sure she’d make up for it later.

CHAPTER EIGHT

While Walkers share the Key World with Originals, we occupy very different spheres. Casual acquaintances and business interactions are acceptable, but strong attachments are discouraged.

Most importantly, revealing the existence and abilities of Walkers is strictly forbidden. Originals cannot understand the scope of our responsibilities and would seek to take advantage of both us and the multiverse, resulting in disaster.

—Chapter Ten, “Ethics and Governance,”

Principles and Practices of Cleaving, Year Five

ELIOT AND I had been coming to the Consort Building for years—as little kids on family outings, and later as eleven-year-olds beginning our training, dropped off by his mom or mine. Eventually we’d graduated to taking the train on our own, once they trusted us not to wander through the pivots riddling Union Station. Class met four times a week, and I learned more in a single session of Walker training than in an entire month of regular high school.

To Originals, the Consort’s headquarters looked like any other office building in Chicago’s Loop. Even the name on the front door blended in: Consort Change Management. Nobody could tell you exactly what they did, but they’d been a quiet, unassuming presence in the city for as long as anyone could remember. My parents drew a paycheck from CCM; they filed their taxes every year, they had health insurance and pension plans. CCM had offices around the globe, entire communities of Walkers hiding in plain sight. The operation was funded by investments, using information gleaned in Echoes. They took insider trading to a whole new level.

We followed our usual path from Union Station, taking Adams across the river, forcing myself not to look at the gray-green water below, waiting impatiently for the light across Wacker.

“Everyone’s going to know,” I said, squeezing the straps of my backpack. “They’re probably talking about me right now.”

The light changed and Eliot hustled me across the intersection, dodging the commuters streaming past us. “Quit dragging your feet. You love it when people talk about you.”

“Sure, when they’re saying how kick-ass I am. This is not one of those times.”

“They probably won’t even know.”

I snorted. “They’ll be thrilled. And it’s going to napalm my class rank.”

Unlike Washington High, where my GPA consistently landed in the toilet, Walker training didn’t give grades. Instead they relied on rankings, and mine was disappointingly average.

Ranking was based partly on fieldwork, which I dominated, and partly on classroom assignments, which I did not. Walking was easy for me. Navigating branches, moving through pivots, tracking signals . . . I moved as swift and sure as an arrow.

Classwork was another story. Nobody gave points for intuition or improvisation, only the meticulous repetition of Consort protocol. Eliot tried to help, but his patient explanations only underscored how differently my mind worked. In the Consort’s eyes, “different” was the opposite of “better.”

My ranking, combined with our final exam, determined where I’d be assigned during my apprenticeship. We could request a position, but the final say, as always, belonged to the Consort. Never before had I realized how much of my future lay in the hands of other people, and the knowledge made me want to kick something. Hard.

We stopped outside the glass doors of CCM. Inside was a nondescript lobby—marble floors, security desk, a bank of elevators, and a few low couches and tables. Our classmates were gathered in the corner, everyone leaning in, still wearing their coats and backpacks.

“Listen,” Eliot said, eyeing the twin guards at the security desk. “When you see the Consort . . . act contrite. Like you regret what you did.”

“I do,” I said, remembering the twist in my gut as the Echo unraveled. “It’s not an act.”

“Good,” Eliot said. “Don’t blame Addie, either. They think she’s great, so it’s logical they’d take her side.”

“That’s nothing new,” I said.

He took my hand. “We don’t want to be late.”

I nodded, and he held open the door.

My skin tingled every time I crossed the threshold of this place. There’s power in secrets, in knowledge hidden away. The deeper they’re hidden, the greater the tension shimmering through the air. This building held secrets Originals couldn’t dream of, and no matter how many Monet reproductions they hung on the walls or how tasteful the jazz they piped in, the hum of power couldn’t be entirely muted.

This time when I walked in, dread curled through me, bitterly cold.

“Del!” Callie Moreno called from the corner. The group turned to gape at me. Muttering something under her breath, Callie shot them a dirty look, pushed off the couch, and strode across the lobby. In the too-quiet room, the heels of her boots rang out on the floor. She gave me a half smile, warm but worried. “Is it true? Logan said you—”

“Delancey Sullivan?” one of the security guards asked, stepping out from behind the desk. Callie’s smile fell away, and Eliot shifted, putting himself between us. “You’ll need to come with me.”

I opened and closed my mouth soundlessly, like a fish thrown onto shore.

“Where?” Eliot asked. “Says who?”

Out of the corner of my eye, I spotted my classmates edging closer, as if they couldn’t catch every word in the echoing lobby.

“To the sixteenth floor,” the guard said, chest puffed out. “At the request of the Consort.”

“Class starts in five minutes,” I said, my voice rasping.

He smirked. “Not for you.”

Eliot turned his back on the guard to look at me, his dark skin shiny with nerves. “I’ll go with you.”

The guard beckoned, and a woman in an identical uniform—badly cut black pants, white shirt with black trim, Taser and other paraphernalia hanging from a thick leather belt—joined him.

As a precaution against creating strong pivots in the building, Consort guards didn’t carry lethal weapons. Before today I’d assumed the stun gun and pepper spray were to protect the Walkers from discovery by Originals. Now, as the second guard stared down my best friend, I reconsidered.

In a nasal, overloud voice, she said, “The summons is for Delancey alone. We will escort you to the chamber. The rest of you will proceed to training as usual.”

Eliot met my eyes, ready to argue.

“I’ve got this,” I told him, trying to keep the wobble from my voice. “See you in a few.”

Maybe they would let me off with a warning. If they did, I’d be a model student for the rest of training. I’d help out at home. I’d be nicer to Addie. Anything, as long as they didn’t take Walking from me.

Our path to the elevators was blocked by my classmates. Behind us, the younger kids were coming inside for their training, some of them accompanied by their parents. As the lobby filled and the murmurs grew, my face went fiery. I’d wanted to be known for my skill, not my screwups.

I kept my eyes fixed on the elevators, tuned out the whispers and snickers, and moved across the room on autopilot. Shame burned through me, hotter with every step. But it wasn’t until I was inside, steel doors sliding shut, that I nearly lost it. The glimpse of Eliot, stricken and sympathetic, was infinitely worse than the onlookers’ scorn.

Given a choice, it seems like pity would be easier to bear than mockery, but that’s not true. Mockery hardens defenses; pity slips through, finds the softest places you have, and slices to the bone.

Pity will break you, every time.

One guard slid a card through a reader and pressed the button for the sixteenth floor. I thought about asking what would happen, but they looked straight ahead, feet braced wide and hands clasped behind their backs. They didn’t seem like they’d welcome a conversation.

I wondered if they knew the full story, or if they’d simply done the Consort’s bidding without asking for details. Probably the latter. Nobody questioned the Consort. Their rulings were absolute, their directives inviolate. Even my parents didn’t challenge the orders they received.

The display counted steadily upward, and I knotted my fingers together as the elevator slowed. The doors opened and my lungs closed.

My parents stood in the cream-and-ebony foyer, their heads bent together. Monty perched on an upholstered black bench, looking around owlishly. He must have been here plenty of times, but he was acting as if he had never seen this place before.

One of the guards prodded me in the back, and I stumbled into the hall. My mother’s head snapped up, her mouth tightening in annoyance. “Del! Why did you run off? I told you we would come in together.”

“And I told you I’d ride with Eliot,” I said, palms sweating. “I can do this without you.”

“You’re a minor,” she said. “The Consort can’t sentence you unless we’re present.”

“Sentence me?” I repeated. “I’m on trial?”

“No, sweetheart.” My father pulled me to his side, like he could protect me from the impact of his words. “The trial’s over. They’ve called witnesses, reviewed the reports . . .”

I jerked away. “I didn’t get to defend myself!”

“Your actions are your defense, Del. Intentions don’t count. Explanations don’t count. The only thing that matters is the end result,” he said.

“Deaf and dumb,” Monty grumbled. “Every one of them.”

Mom shushed him. “Dad!”

He waved her off. “Rose used to say I should have been given a Consort seat. Thought I could do some good. Don’t let them scare you, Del. You’re worth ten of them.”

My mom pinched the bridge of her nose. “Dad, you’re not helping matters. Can you please keep it to yourself until we get home?”

Monty’s disdain for the Consort was nothing new—their failure to find my grandmother was a grudge he’d nursed my whole life. But his words could be twisted if the wrong person overheard.

“I keep all kinds of things,” he said, tapping his forehead with a gnarled finger. It would have been better for him to stay home, and I realized we were short one person.

“Where’s Addie?” I asked.

My dad tugged at the knot of his tie. Cleavers rarely dressed up, and now I understood why. Hard to run in business casual. “She’s inside.”

Sympathy stirred within me, but it was comforting to know I wasn’t the only one on trial. They must have already sentenced her, since she wasn’t considered a minor.

The female guard touched her earpiece and gestured to the twin doors of the Consort’s chamber. “Go in.”

Monty levered himself up with a grunt. My mom helped me with my backpack and coat, handing them over to my dad. She started to say something, but stopped. Instead she tucked my hair behind my ears and sighed, as if it was the best she could do. My dad reached for the door handle, not meeting my eyes.

I started to shake, and the worst-case scenarios I’d been trying not to imagine crowded into my head. Prison. An oubliette. Another cleaving, one I couldn’t escape.

A blue-veined hand closed over mine, cool and reassuring. Monty angled his head toward the door. “Together?”

At least Monty was looking out for me. “Together.”

I looked up at the marble plaque above the chamber doors. The Key World frequency was carved into the polished white stone, a line of peaks and valleys in perfect symmetry. The motto beneath captured everything I’d ever been taught.

To the true song, all honor;

From the true song, all gifts.

For the first time in my life, the lines rang false. Walking was my birthright, my gift, but the people inside that room had the power to snatch it away. My whole future—the only one I’d ever wanted—had narrowed down to a single moment. A single decision.

And it wasn’t mine to make.

CHAPTER NINE

The Minor Consorts number forty-eight, each responsible for a specific time zone on one side of the equator. They govern the branches and Walkers within their territories and are accountable only to the Major Consort.

—Chapter Ten, “Ethics and Governance,”

Principles and Practices of Cleaving, Year Five

THE CHAMBER OF the Minor Consort sounded impressive, but the room itself was spare and anonymous. Institutional gray carpet, white walls, and no chairs except for those behind the table at the front of the room. The three Consort members were already seated, tracking my movements closely. Addie was standing to the side, arms crossed over her stomach.

These Consort members had served for as long as I could remember. They’d probably worked with Monty. Before my grandmother disappeared, he’d risen pretty high in the ranks, leading a team of Cleavers to the most critical Echoes. But he gave no sign of recognizing them.

My mom guided him toward the wall, her voice so soft I couldn’t make out the words. Addie joined them, taking her place next to my dad. She looked wan but resolute. They must have come down hard on her.

“Come forward, Delancey,” said the woman in the center. “I’m Councilwoman Crane.”

I knew who she was. I knew all of them, though we’d never met. The Consort was comprised of three members, one from each section: ethics, science, and cleaving The ethicists were the ones who made the rules and policies; the scientists studied the physics of the multiverse and the Key World; the cleavers dealt with the day-to-day effects and protocols of cleaving. All three were represented on the Consort to ensure their decisions were balanced—all their decisions were unanimous, to symbolically avoid pivots. Whatever my sentence, they’d agreed upon it.

Crane spoke in a faintly scratchy alto. Her white hair was cut short and severe, but her features were soft behind her frameless glasses. She didn’t look kind, exactly, but she did look fair. As the ethicist, she’d be in charge of my sentencing.

I edged to the center of the room and tried to look contrite.

To her left sat another woman, Councilwoman Bolton, the head of the scientists. Her dark hair was as long as mine, arranged in countless tiny braids, heavily shot through with silver and caught in a low ponytail. Her eyes—a harder, sharper brown than Eliot’s warm gaze—seemed to catalog every one of my faults. I curled my toes inside my shoes, and tried to read my future in their faces.

The man on the right was easier to read but no more reassuring. He had a narrow face, steely hair swept back from a high forehead, and a strong nose. On some people it would have been aristocratic. But he caught sight of Monty, and for an instant his lips peeled back. Aristocratic turned arrogant. Councilman Lattimer, who ran the Cleavers.

Before today these people had been only names—last names, no less, unlike the rest of the Walkers. They’d been printed across the bottom of the letters I received every June, congratulating me on another successful year and welcoming me to the next round of my training. They’d been mentioned over dinner, when my parents were discussing a policy change, or in class, during our unit on governance. I’d never envisioned them as real people.

Now they seemed even less human.

I looked back at Monty, hoping for reassurance. He’d deliberately turned away from the Consort, tugging fretfully at the buttons on his coat, inspecting the door as if he could escape.

“Let us begin,” said Councilwoman Crane.

I locked my knees to keep them from giving out.

“Yesterday we received a report stating that, on an accompanied Walk, you unraveled a world resonating at the specific frequency of . . .” She read from a paper in front of her, rattling off a number at least twenty digits long, complete with decimals and exponents.

“It was an accident,” I protested, my voice as high and plaintive as a child’s.

“Within every accident lies a choice,” Bolton said, her expression stern.

Before I could say anything else, Lattimer held up a hand. “We are not concerned with your excuses or opinions. Only the outcomes and evidence matter here.”

Councilwoman Crane continued, setting the paper aside. “We’ve spoken with your instructor. The parameters of your assignment neither required nor permitted direct contact with the strings. Our investigators confirmed the frequency in question has ceased transmitting. According to the witness statement, you are the one responsible.”

“The witness statement?” I whirled, but Addie wouldn’t meet my eyes. “You sold me out?”

“As the only other Walker present, her testimony was required,” Bolton said. “Based on the findings of our investigators, we believe her statement to be accurate and reliable.”

Addie nibbled on her thumbnail, head bowed. I took a step toward her, and the guards at the door both shifted—hands on weapons, faces impassive, intent clear.

I dug my fingernails into my palms, trying to see through the haze of anger. It wasn’t enough for Addie to be perfect, to be the one everybody fawned over. She had to screw me over, too.

Councilwoman Bolton read from her own paper. “Your interaction with the Echo child was unnecessary and increased the existing damage. You ignored the direction of your accompanist, and your actions endangered her life. Your cleaving was improperly conducted, resulting in a weakening at the cut site of the pivot.”

“Any one of these is a serious infraction,” Lattimer said. “To commit so many on a single Walk indicates a tendency toward recklessness that does not bode well for your future.”

A hint of a smile snaked over his face and his gaze flickered to Monty, then back to me. “You are suspended from your Walker training for the remainder of the year. You may not attend classes with your cohorts. You may not Walk alone, or with anyone but licensed family members.

“At the conclusion of your suspension, you will be expected to take the final licensing exam with your classmates. If you pass, you may continue on to your apprenticeship. If you fail or violate our terms, you will repeat your fifth year while your peers move on.”

The room wavered along the edges. “The entire year? How am I supposed to pass the exam if I can’t go to training?”

“That responsibility will fall to your family. We’ll expect a weekly report of your lessons, to ensure you’re receiving proper instruction. Naturally, this would be in addition to your parents’ usual duties.”

My parents couldn’t find time to help with a homework assignment, much less an entire year of training. The fifth-year exam was notoriously hard—cumulative over all our years of training, covering every aspect of our work. The last three months of class were essentially a giant cram session, and Shaw made sure we were prepared. Without his help, I’d fail.

By June my classmates would have their licenses. Eliot would be off to his apprenticeship. Everyone would know I’d been left behind.

Walking was the only thing I was good at, and they were taking it away. Something inside me twisted sharply at the loss.

Councilwoman Crane cleared her throat, waiting for a response. Shock had stolen my words, and I eyed her mutely.

Her expression thawed. “Do you agree to comply with the terms of this sentence? The alternative is to permanently forfeit your right to Walk.”

People weren’t kidding when they said the Consort went out of their way to minimize choices. I’d do anything to be a Walker, and they knew it. I looked back at my parents, who appeared solemn but unsurprised. Maybe even relieved. Next to them, Addie stood frozen, fingers pressed to her lips.

“I object!” shouted Monty. My mom took his arm, but he shook her off, stomping past me toward the table. Crane and Bolton exchanged knowing looks, while a mottled red crept up Lattimer’s neck.

“Overruled,” Crane said calmly. “This is not a courtroom, Montrose. Surely you haven’t forgotten that much.”

“She’s got more talent in her little finger than any of you. I trained her myself.”

“Did you?” said Lattimer. He studied me with fresh curiosity, like a frog in biology class, right before dissection. “Quite the student she’s turned out to be.”

“We gave this matter considerable thought. We took into account her age and her abilities, your family’s service, and your . . .” Crane trailed off, searching for the right word. “. . . sacrifice. It is our hope she will use this time to grow into her talents. But we have made our decision, and now she must make hers.”

She shifted her gaze back to me. “Delancey?”

Sometimes, in the instant an Original makes a choice, you can feel the pivot forming. The air snaps and shifts, as if the world is breaking open to make room for the other reality taking shape. It doesn’t happen for Walkers. Our pivots are too weak to last, and once our choice is made, we can only imagine what might have been.

So I said yes, and listened to the silence.

CHAPTER TEN

WELL, THAT COULD have gone worse,” My father said after we filed out, trying to sound upbeat and missing by miles. He put his arm around my shoulder, but I yanked away.

“They kicked me out,” I snapped. “I’m going to fail the exam. How could that have gone worse?”

Monty patted my hand.

“They could have sent you to an oubliette,” my mother said sharply. Addie stood next to her, shoulders curling inward. “You should be—” Behind them, the chamber door swung open again.

“Winfield, Foster,” said Councilwoman Crane, leaning on an ivory-handled stick. “We have another matter to discuss.”

My parents exchanged glances. “Wait here,” Mom said. “And behave yourselves. That includes you, Dad.”

“Foolishness,” Monty mumbled when they’d left, crushing his hat in his hands. “Hidebound foolishness.”

“What do you think they’re talking about?” Addie asked, ignoring him.

“Probably what a bitch you are,” I said. “You got off scot-free, didn’t you? That’s why you were so eager to turn me in. You wanted to cut a deal?”

“There was no deal,” she said, flushing pink. “They asked me what happened. I told the truth.”

“Your truth.” Not the same thing. Truth is as fluid as water, as faceted as diamonds, as flawed as memory, Monty used to say. People saw what they needed to believe in the moment. Not untrue, he’d remind me. Just not the entirety. And Addie needed to believe I was the villain. “I’m suspended, thanks to you.”

“Thanks is right, you little brat,” she shot back. “Lattimer was convinced you did it on purpose. Unsanctioned cleavings can be tried as treason, Del. Same with lying to the Consort. So, yeah. I told them what an idiot you were, and they went easy on you.”

“Treason?” I said, ice filling my veins.

“You’re welcome,” she said grimly as Lattimer stepped into the corridor, immaculate and unsettling.

“I’m surprised to see you here, Montrose. Goodness, it’s almost like old times.” He said the words with relish. “All we’re missing is Rose.”

Monty jerked, and he leaned in like he was telling me a secret. His voice, however, carried through the empty hallway. “Rose never liked him.”

A vein in Lattimer’s temple pulsed, but he took in Monty’s threadbare cardigan and disheveled hair, the unsteady hands and stooped shoulders, and smirked. “Her judgment wasn’t exactly sound, was it? Otherwise she’d still be with us.”

To my surprise, Monty didn’t protest that my grandmother was coming back. He sagged visibly, murmuring, “Like old times.”

“Is he often like this?” Lattimer asked Addie.

“Some days are better than others,” she hedged. “He’s tired.”

“Of course,” he replied. “He was quite talented, you know. It’s a shame, what his searching has done to him.”

“What you’ve done,” Monty growled.

There was an awkward pause before Addie stepped in. “I’m so sorry, Councilman. He gets confused.”

“I see,” Lattimer said, sounding sympathetic. He patted Monty’s shoulder, ignoring the way he twitched. “I merely wanted to check up on you, old friend. I’d best return to my colleagues. Duty calls, you know.”

He reached for the doorknob and my jaw unclenched.

Lattimer paused and turned back. “We appreciated your forthrightness this afternoon, Addison. One year left in your apprenticeship, I believe?”

She bobbed her head. “Yes, sir.”

“Excellent. If you continue to impress us as you have, you’ll have quite a bright career ahead of you.”

“Thank you, sir,” she mumbled.

“As for you, Delancey,” he said, keeping his eyes on Monty. “You’d do well to pick your role models more carefully, if you hope to have a career of any sort.”

The door shut behind him with a soft click.

“I really get the sense he’s rooting for me,” I said.

“He’s bearing a grudge,” Monty said, back to his old self. “And you’ve been caught up in it.”

“What kind of grudge?” Addie asked.

“An old one,” Monty said. “Ancient history.”

I didn’t believe that any more than the helpless, muddled routine he’d put on for Lattimer’s benefit. Both ignited my curiosity.

He jammed the battered hat on his head. “Let’s go. The sooner we’re away, the better.”

“Mom said to wait,” Addie protested.

“Stay if you like,” he told her, then directed his words to me. “There’s nothing here for either of us now. Are you coming, Del?”

Monty had never steered me wrong before, so I went.

CHAPTER ELEVEN

When visiting an Echo world, interaction with its inhabitants should be limited to frequency analysis. Do not engage with Echoes in a frivolous manner or for personal gain.

—Chapter Three, “Echo Properties and Protocols,”

Principles and Practices of Cleaving, Year Five

DINNER,” MOM SAID when we arrived home. “Del, set the table.”

I threw my coat on the couch. “I’m not hungry.”

“Dinner,” she repeated.

My mother had a thing about the whole family eating dinner together. Even when we were little and my dad was out cleaving, he made a point to be home for the evening meal. Sometimes we ate at four in the afternoon, sometimes nine at night, but it was always the five of us, clustered around the big pine table. A constant.

No one except Monty ate much. Finally I asked, “Which one of you is going to tutor me?”

I was hoping for my dad. A First Chair, he led teams of Cleavers into the most dissonant worlds, managing their unraveling. There was nothing he liked better than a lost cause, everyone joked.

Suddenly it didn’t seem so funny.

Still, it was better than working with my mom. A navigator, she analyzed pivots branching off our part of the Key World, determining which Echoes needed cleaving. If she was in charge, I’d be stuck in her office for the next six months, charting frequencies and crunching numbers.

She rearranged her silverware, took a sip of water. Stalling. I knew the move, because I was an expert at it. “Your father and I are working on a project that will require a lot of our attention.”

Addie straightened, like a hunting dog who’d scented a rabbit. “Is that why the Consort wanted to talk to you?”

My dad nodded. “The Major Consort is sending in teams from around the country, and they’ve asked us to coordinate.”

“The Major Consort? That’s huge,” Addie said. “What kind of project?”

“A classified one,” Mom said. “We’re hoping it’s a short-term assignment, but for now, it’s our top priority.”

Which meant I was not.

“There’s no reason your training has to suffer,” my dad put in, seeing my expression. “While we’re handling this, Addie can work with you.”

I slammed my water down. “Are you kidding? She’s as much to blame as I am!”

“I am not!” Addie shouted. “You were supposed to listen to me, and you ignored every word I said.”

“If I’d done what you told me to, we never would have gotten out. You’re mad because you choked, and I had to save your ass.”

“I’m not the one who’s suspended, am I? I don’t want to train her! What about my apprenticeship? I’m supposed to be focusing on my work, not holding her hand!”

“Girls!” My mom pinched the bridge of her nose. “Enough. We know it’s not an ideal situation, but it’s not up for debate.”

“The Consort said you were supposed to teach me,” I said, desperation creeping into my voice. “Not Addie.”

“Technically, they said ‘your family.’ Addie qualifies.”

“Unfortunately,” I sniped.

Addie made a face. “The feeling’s mutual.”

“The Consort agrees this is the best solution for now. In fact, it was Councilman Lattimer who suggested you two work together. It should only be for a few weeks,” my father said.

Monty blew a raspberry, and Mom rolled her eyes. “Dad, it’s a good thing. The councilman must think highly of Addie to give her this kind of responsibility. It’s an honor, really.”

Addie didn’t look honored. “Why am I being punished for Del’s mistake?”

“You were responsible for her during that Walk,” my dad said mildly. “It seems fair you should shoulder a portion of the consequences.”

“Dad, why can’t I tag along with you?” I turned to him in appeal. “I’d learn a ton. Way more than I will with Addie.”

“No can do, kiddo.”

“But . . .”

“I can watch over the pair of them,” Monty said abruptly. “Be good to keep my hand in. And I’ll bet I know some tricks that aren’t in your books, Addie-girl.”

“That’s not really the point of the exercise.” My mom set down her fork and frowned at him, but he was already drifting.

“I should exercise more often. Good for the heart. My heart,” he said, his face softening. He stood up, his napkin dropping to the floor. “I’ll be off, then.”

“Dad, no.” Mom scrambled after him. “Sit down.”

“Rose needs me,” he said. “She’s out there, Winnie. Your mother. I promised I’d find her.”

My mother was many things in our family—the glue, the backbone, the compass—but mostly she was the rock. She made the hard choices and the tough calls. We went to my dad when we scraped a knee, to be fixed with a Band-Aid and a kiss and an oatmeal cookie. We went to Mom when we broke a bone, to make sure we got to the emergency room safely. She moved through the world with such determination, such forcefulness, it was easy to forget that when my grandfather had lost his wife, she’d lost her mother. Her hand went slack on Monty’s arm.

He took advantage of the moment and pulled away, hitching up his khaki pants, hand outstretched to find a nearby pivot. My dad tensed, ready to grab him, but I knew better. Confront Monty, and he’d bolt. Distraction was key.

“Brownies,” I said cheerfully. “There are brownies for dessert. I saw them earlier. And ice cream. You don’t want to miss brownies à la mode, do you?”

He paused. “À la mode.”

“It means with ice cream,” Addie said.

“I know what it means.” He smoothed the wisps of white hair sticking out at odd angles and considered the offer.

“You can have the corner piece,” I wheedled.

Stiffly, like he was doing us a favor, he came back to the table. My mom blew out a breath, and my dad took her hand in his.

Without a word Addie rose and started dishing out dessert. Midway through his brownie, Monty spoke again. “It’s settled, then. I’ll supervise the girls.”

“I don’t need supervision,” said Addie. “I’m the supervisor.”

My parents had one of their wordless conversations—raised eyebrows, pursed lips, the tiniest of head tilts—a duet in a key only they understood. Reluctantly my dad said, “You’d need to keep a close eye on them, Montrose. Especially Del.”

I scowled, but my mom gave a warning shake of her head—and this time the message was perfectly clear. Don’t argue.

The idea of Monty in charge was ludicrous. Most days he couldn’t remember what year it was or where we kept the milk. But he’d definitely be more fun than Addie, whose expression teetered between wounded pride and outrage at the thought of being replaced.

“Fine by me,” I said. “I like spending time with Grandpa.”

Mom looked at Addie. “Well?”

She smiled through clenched teeth. “Sure.”

“Excellent. I’ll let the Consort know.” Mom dusted off her hands, like everything was in perfect order once again.

Monty wandered away from the table, my father close on his heels. Addie flounced upstairs to sulk, and I headed to the attic.

Addie and I had shared a room until I was ten, when my parents had offered up the third-floor attic. I’d moved the same afternoon. It was boiling in summer and freezing in winter, but it was also private. The stairway, narrow and steep, tended to discourage visitors.

The room was an unfinished mishmash, with oddly shaped windows and slanted ceilings. I’d filled it with castoffs and pieces “liberated” from the rest of the house—a bottle-green chaise, a tattered leather chair, an enormous trunk with brass fittings. I’d propped an old door on sawhorses to make a desk, but you could barely see it under the piles of sheet music and maps.

Along the rafters and over the windows, I’d strung origami stars, my own twisting, multicolored galaxy. They jumped as I slammed the door and snatched up my violin.

Nothing took me away from myself like Bach. The music, a dense, exacting flurry of notes, demanded my full attention. The violin had been my grandmother’s, and her grandmother’s before that. The sound poured out, rich and sweet and heartbreaking. It was easy to lose myself in the finger work, to sweep the bow over the strings with the anger I hadn’t been able to show the Consort.

Midway through the second movement, my mom let herself in.

“Very nice,” she said. “But isn’t that section marked largo?”

Of course she’d want me to slow down. I sped up for the last few measures, ending with a flourish. “I’m allowed to improvise, aren’t I? Or is the Consort monitoring my orchestra grade?”

She sighed. “You might not believe this, but we’re looking out for you.”

I concentrated on loosening the bow and tucking it away.

“No one doubts that you’re very talented, but you don’t apply yourself. Walking isn’t fun and games, Del. It requires discipline and practice. It’s the same as your music—you have to know the rules before you can break them.”

I could play the Bach Double backward—and had, on a dare from Eliot. My mom wouldn’t have seen the humor in it. “Monty breaks tons of rules.”

“Look where it’s gotten him. If you need a lesson in why our rules are important, he’s an excellent one.” She lowered her voice, as if he might hear us. “He’s getting worse.”

I plucked at the violin strings, letting the sound travel through me. Underneath, strong as ever, was the frequency of the Key World. Monty had been my first teacher, and I didn’t want to think about his decline. “He’s not that hard to manage, if you’ve got something he wants.”

“The only thing he wants is your grandmother. I know you and Addie don’t need a chaperone, but he does.”

Understanding dawned. “You want us to watch him,” I said. “Not the other way around.”

“Addie can supervise you both, and ultimately, she’s in charge. But he listens to you better than any of us. He always has.”

True enough. After Addie had started school, Monty and I were often left alone together. “Walk with me, Del,” he’d say, holding out his hand, and we’d go exploring. Echoes had a music of their own, he swore, and he’d taught it to me alongside our piano lessons. I’d listened to him back then, and now he was returning the favor.

“We’re going to have to do something about him, but . . .” She trailed off, touched the pendant hanging around her neck. A miniature tuning fork, identical to Addie’s. Every Walker had one. Every licensed Walker. “I’m not ready to send him away.”

To a facility. A “home” where he’d be supervised and medicated, tethered to the Key World. Nothing would kill him faster.

“Don’t look at me like that. We’re hoping that working with you will keep him out of trouble.” She reached out, tucked a lock of hair behind my ear. “You look like her. My mother.”

I’d seen the picture in the hallway, but not the resemblance. It was my grandparents’ wedding portrait, my grandmother lifting her chin to face the camera straight on. Everything about her seemed strong and forthright, from her dark, intelligent eyes to her generous smile. She was the kind of beautiful that people called striking. The best I could hope for was “cute,” but people were usually talking about my height, not my looks. I heard “lovely” a lot too, as in, “Del could be lovely if she’d do something about those clothes/that hair/her attitude.”

“Is that why I’m his favorite?”

She straightened the sheet music propped on my stand, tracing the intricately carved mahogany. Like the violin, it had belonged to my grandmother. Monty had insisted I use them; they were my only connection to her. “You look like my mother, but you and Monty are peas in a pod. You’ll watch out for him, won’t you?”

I snapped the case shut. If it would keep him out of a home, how could I say no?

Later, while my family slept, I stared at the stars spinning from the rafters and tried to imagine what my life would be like if I failed. If I never Walked again. Every choice irrevocable, every decision fixed. Never seeing the beauty and possibility of Echoes again. How did people live like that? The thought made my skin feel two sizes too small, and my legs prickled like pins and needles.

Sometimes I worried about liking the Echoes too much. There’s a danger in being drawn to something that’s not real, in giving yourself to something you can never be a part of, instead of making your life where you are. But those infinite worlds, with their infinite potential, beckoned irresistibly.

I slipped out of bed, back into my bulky cardigan and a pair of old jeans. They were more holes than denim, but the fabric was worn to blankety softness. I twisted my hair back into a knot, tucked a pack of notepaper into my pocket, and crept outside.

Maybe it was stupid to go out by myself, especially after the Consort had told me not to. But the thought of being under Addie’s thumb for the next six months was suffocating. I wanted one last night where my choices were my own.

I took small steps, shifting through incrementally different worlds, drawing out the feeling of power and freedom. I listened with my whole body—skin and muscle and blood and bones—my entire being attuned to the music of the universe. Most Walkers said the other worlds were full of noise, but they were wrong. There was beauty in it, if you listened.

The doughnut shop was closed for the night. The streetlights turned the plate-glass window reflective, and I looked pale and wild-eyed. But I looked happy, too, in a way I often didn’t in the mirror over my dresser.

A few blocks away I could hear the twang of guitar and the throb of bass. The show at Grundy’s. Simon’s invitation. He might have changed his mind. He might not remember he’d asked me . . . but I wanted him to.

A light rain started to fall, and I headed toward the music, looking for Simon.

Simon and trouble.

CHAPTER TWELVE

Direct contact with an Echo will intensify your perception of a world’s frequency and heighten their awareness of you. Therefore, it is essential to limit physical contact with individuals in Echo worlds.

—Chapter Five, “Physics,”

Principles and Practices of Cleaving, Year Five

DIM LIGHTING. ALT-COUNTRY band on the cramped stage. The smell of sweat and cheap beer and fresh pizza. The booths were filled with chattering women, biker couples, and Echoes of my classmates, wedged five to a side in booths meant to fit three. I veered to the opposite end of the room, tapped the bartender on the arm, and ordered a rum and Coke. When he asked, I passed over my fake ID—much higher quality than Park World Simon’s—and feigned boredom while he scrutinized it.

Drink in hand, I eased closer to the stage and leaned against a wooden post. The band was good—exactly the right amount of ache in the singer’s alto, raw but not emo, with the bright, unexpected notes of a mandolin weaving through. I didn’t get to simply appreciate a song that often; some part of my brain kicked in and started analyzing it, as if a frequency might be hidden within the notes.

I sipped my drink, letting the sugar bolster me and the alcohol relax me, and scanned the crowd. No Simon. Maybe he’d decided not to come. If so, there was an Echo nearby where he’d done the opposite. I could find it if I was willing to put in the effort. Then again, tracking him down across a bunch of random realities was a lot of work for a guy I barely knew—in this universe or any other.

The glass was sweating. I wiped my hand on my jeans and tried not to feel hurt that he wasn’t here. It was late. It was a school night. The practical thing to do was go home and crash.

“Drummer’s not bad,” Simon said from behind me, so close his breath ruffled my hair.

Practicality is overrated.

Pushing back the smile threatening to break loose, I turned. “Most people focus on the guitarist. Or the singer.” I had a vague memory of Original Simon playing drums when we were in junior high. “You play?”

“Sometimes.” He braced one arm against the post, silver spike glinting at his wrist. “I was starting to think you stood me up.”

“I didn’t realize this was a date.” I hadn’t even been certain he’d remember me. Then again, it had been less than twelve hours since we’d spoken. Not long enough for him to forget, but plenty of time for my life to be turned inside out. “You never asked me.”

“I didn’t?” The light was too low to read his expression—if he was teasing, or disappointed, or genuinely curious. All I had to go on was the sound of his voice—a little rough, a little warm. “Serious mistake on my part. I could ask you now.”

“We’re already here. The timing’s off.” Curious how a different Simon made me different too.

“What if we went somewhere else? Somewhere quieter?”

I choked on my drink. “That’s kind of fast,” I said. “Even for you.”

“For coffee, Del.” He laughed, his eyes full of mischief. “What did you think I meant?”

“Nothing.” I felt the blush spread along my cheeks and hoped he wouldn’t notice. He offered me his arm, and I took it, the muscles like iron under my hand. He sounded the same as he had in front of the bakery—dissonant but stable, a steady rhythm that matched my pulse. Already his frequency was etched in my mind. “Coffee?”

The corner of his mouth curved up. “For starters.”

I punched him lightly, but didn’t let go. “Was there a basketball game tonight?”

“No idea.” I thought I saw a momentary sadness in his expression—but then it was gone, a trick of the light. “Not my thing these days.”

He shrugged into his coat, the black leather well-worn and supple, his shoulders broad and straight. When his hand found mine, I didn’t pull away.

The rain fell steadily, silver against the streetlights. The cold air felt good after the overwarm room, and I breathed deeply as we walked. Simon said, “You took off pretty fast today.”

“I needed to get home.” I stopped under an awning. “You know, I don’t want coffee.”

“No?” He joined me, the water beading like mercury on his coat and hair.

I shook my head, feeling dizzy—the frequency rippling along my skin, the air damp and clean, Simon stepping close to me, smelling of leather and rain.

“Why did you come back?” he asked.

“You invited me.”

He tugged at the clip holding up my hair, and it tumbled around my shoulders in a rush. “You liked the music, but you left before their set was over. You ordered a drink, but barely touched it. You’ve said yourself it’s not a date, and you don’t want coffee. Did you come out here just to walk around in the rain?”

“You got all of that from ten minutes in a badly lit pizza place?”

Lately, no one noticed me, except to point out what I was doing wrong.

“So,” he pressed. “Why are you here?”

This world wasn’t mine. I could spill out my secrets and leave, and no one would ever know. He might remember me now, but in a few days I’d drift from his mind like smoke. But for the time I was here, I could forget myself.

“I’m grounded, kind of. Starting tomorrow, I’m pretty much under twenty-four-hour surveillance.”

“You figured you’d break out? One last night of freedom?”

“Something like that.”

He touched my chin. “Better make the most of it,” he said, and when I looked up, he was only inches away, the heat of his body chasing away the cold. He pushed my heavy, rain-soaked hair back, his palm brushing my cheekbone. His gaze fixed on my mouth.

I couldn’t look away from his smile, the way it tipped to the side, challenging me. Not a perfect smile—there was the familiar scar at the corner, and his front teeth were the slightest bit crooked. The imperfections kept him from being too pretty, the same way the faint air of recklessness around him kept him from being too nice.

Nice had never been my thing.

It wasn’t like I’d never been kissed. But I’d never had a guy look at me with such single-mindedness, the entirety of his attention on the scant space between us.

He touched his lips to mine, a silent question. His dissonance drifted around me like dust motes, heightening my senses, and I leaned in and answered with another kiss, my fingers clutching his coat. The air seemed warmer, but it wasn’t the air; it was Simon, pulling me closer, and my blood thrilled the way it did when I Walked into a world for the first time, so much mystery and possibility.

Not real, I tried to tell myself, but he felt real—entirely solid and strong and alive as his arms wrapped around me, anchoring me against him as the world started to spin. He tasted like mint and secrets, and I opened my mouth to his, craving more as his fingers traced languid circles down my back. I shivered at the sensation, tried to close the space between us completely. He broke the kiss, and tucked my head under his chin, his breathing ragged. “You’re cold.”

“I’m fine.”

“My car’s over there,” he said, jerking a thumb toward the Jeep. “We could get out of the rain. Go someplace private.”

I rubbed a hand over my mouth, where his lips had been a moment ago, the taste of him still fresh, my pulse unsteady.

“Or not,” he said, dark eyebrows lifting. “Your choice.”

Around us, I could hear the fissures forming, a hundred pivot points created by a single kiss, the universe cracking wide because of this one instant, this one boy.

Time is not static. You can never get a choice—or a moment—back. The best you can do is witness the effects.

I wanted the moment. Every nerve I had was screaming at me to take Simon’s hand, get into the car, and drive.

Not truly Simon, though. This Simon was an Echo, and tomorrow I’d have to sit behind his Original in class and pretend like I didn’t know the feel of his hands or the fit of his mouth. I’d have to watch his eyes pass over me without a hitch, because this never would have happened.

I couldn’t stay.

Already the frequency was ringing in my ears, competing with the thudding of my heart. In two hours I’d have a headache. In three, a migraine. By sunrise I wouldn’t be able to find my way home. I’d Walked too much today.

I drew a piece of paper, dark blue on one side, silver on the other, out of my pocket. It was damp from the rain, the creases soft edged. Simon watched as the star took shape in my hand.

“I’ll take that as a no?”

I finished the last fold and set it on the windowsill. I didn’t need a breadcrumb to find this world again. It was proof of this moment, something that wouldn’t disappear when I did.

“Another time,” I said, only half-believing it, and went up on tiptoe to kiss him again. His hands tightened on my hips, holding me fast as his lips traveled along my jaw.

“You don’t want to leave.”

“Never said I did.” I pushed away, legs and resolve both shaky. “See you around.”

“I’ll drive you,” he said, catching my hand.

I disentangled my fingers from his. “Thanks, but I’ll walk.”

As I rounded the corner, I looked back through the pouring rain. I wanted to see his face one more time, while he remembered I existed.

He’d picked up the star. He stood under the awning, spinning it between his thumb and forefinger, his eyes never leaving me.

CHAPTER THIRTEEN

While a Walker’s decisions create pivots, our inability to form Echoes means the pivot is unable to sustain itself; almost immediately, the newly formed world is reabsorbed by the parent branch. This phenomenon is called “transposition.”

Transposition may also occur when Originals or Echoes make a choice that does manifest in a significant frequency change.

—Chapter One, “Structure and Formation,”

Principles and Practices of Cleaving, Year Five

“WHERE WERE YOU last night?” Eliot asked as we trudged toward the cafeteria. “Didn’t you get my texts?”

“Sorry. I crashed early.” Guilt nibbled at me. First a secret, now a lie. I hadn’t seen Eliot’s messages until I’d returned from Doughnut World, too late to reply. And he would not be thrilled to hear I’d already violated my probation to make out with Simon’s Echo.

I changed the subject. “What happened after I left last night?”

“Left” wasn’t quite accurate, but it sounded better than “After the Consort guards escorted me to my doom.”

Eliot looked away, and I wondered how much he was holding back to spare my feelings. “Just regular class. Boring without you.”

“What are you working on next? More break analysis?” The answer would only make me feel worse, but I couldn’t help asking.

“For another week or so. Shaw said we’ll start inversions soon.”

I ground my teeth. “It’s so unfair. I’m stuck with Addie for the next six months while you’ll be off having adventures and kicking ass.”

“I’m only the navigator,” he said. “Asskickery is your department.”

I jammed my hands in the pockets of my sweater. “Do you think I can pass the test? I’m going to miss out on all the fieldwork.”

“Addie’s good at fieldwork,” he said. “She was ranked first in her class, wasn’t she?”

“Naturally. You know how she is. It’ll be all textbooks and essays. I’m screwed.”

He didn’t contradict me. “We need to figure out why the Echo deteriorated so quickly.”

“The Consort doesn’t care. They thought I did it on purpose.” My impulse in that moment hadn’t been to cleave, but something else both foreign and familiar, a new verse to a song you knew by heart. “The only reason I’m not expelled is because Addie told them I was too dumb to know what I was doing.”

“They listened to her?”

“Who wouldn’t?” I said bitterly. “Now she’s in charge of my training. She has to submit progress reports each week. Isn’t that a conflict of interest? She turns me in and gets to grade me?”

“Hold up.” He shoved his glasses farther up his nose and sat down at one of the couches clustered around the student commons. “I need to think.”

While I waited for his latest flash of brilliance, I studied the trophy case on the far wall, crowded with evidence of Simon’s basketball prowess. State championships and tournament wins, nets draped over the tops of their first-place trophies. Hanging behind them were team pictures, groups of tall, broad-shouldered boys wearing royal blue and matching scowls. It might be a game, but basketball was serious business around here. Even Simon looked solemn and determined . . . until you saw the faint curve at the corner of his mouth.

I thought back to the way Echo Simon had smiled at me last night. That had been a game too, in a way.

Eliot coughed, and I jumped like he’d caught me doing something wrong. “We need to prove you’re not at fault. If we can do that, they’ll have to review your sentencing. They’d reinstate you.”

A loosening in my chest, the faintest stirrings of hope. But hope was a dangerous, fragile thing, easily shattered. I couldn’t afford it.

“Nice plan, but the entire Echo’s gone. If there was any proof, I destroyed it.” I shuddered, remembering the melting sky and flickering children.

“Records,” he said, with the same patient tone he used when explaining my trig homework. “Your mom’s map. Frequency samples from previous Walks. Even similar branches might have relevant information. The Consort adds terabytes of data to the Archives every day. I’ll bet you anything the answer’s in there.”

I didn’t know how much a terabyte was, but it sounded big. And time-consuming. And like a very, very long shot. Hope fluttered again and I tamped down on it. “Addie’s not going to let me spend my suspension going through records. She’s got half the lessons planned already.”

“I’ll take care of the research,” he said, holding open the cafeteria doors.

“What am I going to do while you’re off scouring the Archives?” The noise and bustle of the cafeteria was overwhelming, the smell of steamed hamburgers and canned green beans turning my stomach.

“Funny you should ask,” he said. “I have a theory I want you to test.”

The tension left my shoulders. Eliot had theories about everything, and he was forever asking me to test them. Sometimes this turned out well, like when we figured out how to give people earworms by amplifying the Key World frequency in Top 40 hits. Sometimes it resulted in a sprained ankle and dislocated shoulder, like when we were eight, and I conclusively disproved his idea that you could fall through a pivot if you jumped from a high enough distance. Taking a seat at our usual table, I said, “I’m listening.”

“Watch.” He pulled out a sheet of paper and sketched the floor plan of the cafeteria. “Three pivots since we walked in.” He circled three separate places—one just outside the doors, another at a table full of sophomore girls, and a third near the cash register—and hummed their frequencies.

I closed my eyes, letting the chatter of the room recede. “More than that. I’ve got at least a dozen.”

“Half of those are diminished,” he said confidently. “They’ll blend back in any minute. The other three are off-key but stable. Forget them.”

“How can you tell?” I stared at him. Most Walkers had to be standing in an Echo to judge its stability. Even I couldn’t do it from this distance.

“Because I have a map.” With a flourish he produced his phone, a prototype with a screen bigger than my hand. “And I need to test it.”

“Gimme.”

He handed it over. Tiny lights dotted the screen, like the stars on a clear night. “How does it work?”

“It’s like a GPS. Instead of reading satellite information, it uses the microphone to plot nearby frequencies. Stronger frequencies are displayed as bigger circles, unstable ones flash, and pitch correlates to brightness.”

“Big, bright, flashing circles are bad? Small, dim, steady ones are good?”

He ducked his head. “I know it’s not subtle. . . .”

“Since when have I cared about subtle? You’re a genius!” I threw my arms around his neck. “A map that updates in real time? You’re going to be famous.”

He hugged me back for a second, then pulled away, almost bashful. “I don’t need to be famous. I haven’t even shown it to Shaw yet.”

“Why not? Once he sees it, you’ll own the class rankings.”

“There are a few bugs in the software I’m trying to work out. If I install it on your phone, do you promise you’ll use it?”

His tone was urgent, and I frowned. “Sure, if it helps you test it out. What are you so worried about?”

He shrugged. “That Echo deteriorated way too fast. It could happen again.”

“Park World was a fluke.”

“A fluke that almost killed you. I’ve been checking Echoes in the same frequency range, and they seem fine. But this will tell you if a world is too dangerous before you cross.” He stared at his sketch of the cafeteria and tapped the biggest of the pivots. “Use the map, Del. Promise.”

A burst of laughter from across the room distracted me—Simon, holding court at one of the big round tables near the windows, his chair tipped back on two legs, completely unaware of my presence.

Why would he notice me? He hadn’t been the one to kiss me breathless in the rain. Last night was a secret known only to me and a boy who wasn’t real.

Bree snuck up behind him, covering his eyes with her hands, and the chair dropped down with a thud. She let go, giggling as he reached back and caught her hand. It was the kind of casual gesture I was terrible at reading: Were they flirting? A couple? An actual couple?

Simon always had a girl on his arm. Frequently blond, typically adorable, and almost never serious. Probably Bree was no different. Until I saw the way her free hand toyed with the collar of his shirt—playful on the surface and possessive at the core.

“No time like the present,” I said to Eliot, pushing away from our table. “Let’s take your new toy for a test run.”

“It’s not a toy,” he grumbled. “It’s a serious piece of scientific equipment.”

“It’s so shiny!” I trilled, bumping my hip into his. Turning away from Simon, I headed toward a group of drama kids abuzz about tryouts for the winter play. A dozen pinpricks of light sprang up on the screen.

“There,” he said, pointing to one of the circles. “Something’s different.”

“Somebody changed their mind about auditioning?” I murmured.

“Probably. Tryouts spawn a lot of pivots—so many possible choices.” He gestured to the twinkling display.

“It’s like a cheat sheet.” Only I wasn’t breaking any rules, for once in my life.

He zoomed out on the map and pointed. “Over there, see? This circle’s getting bigger.” I followed him out the doors to the water fountain. The rent in the air was easy to see, if you squinted. Without thinking, I brushed my fingers over the edge. The vibration felt as though it was calling to me.

“What triggered it?”

He peered at the map, then around the hall, nudging his glasses up again. “Not sure.”

“Let’s go look.”

Eliot groaned. “No way. What if we get caught?”

“Who would catch us?” The hallway was practically deserted, and it was such a strange sight—a person disappearing into thin air—most Originals assumed they hadn’t been looking close enough.

“We have class in five minutes.”

“Five minutes,” I said. “Add three more for passing period, that’s eight. Bet I could find the source in eight minutes.”

“Del . . .” He stopped fiddling with the phone.

“See you in eight,” I said, and slipped through the gap.

The Echo looked identical, and the frequency warbled, gradually shifting away from the Key World like a violin part played by a cello. As events here diverged from the Key World, the threads of this reality would settle into place, taking on their final resonance.

I scanned the room, looking for clues to explain why this world had branched off ours.

Finally I spotted it: Beneath the water fountain was a stack of note cards, right where Eliot had been standing. They must have fallen out when their owner stopped for a drink. I picked them up, and the key change traveled up my arm.

Notes for a test, I figured, looking at the neat lines of chemical equations in a round, cheerful hand. If there’d been words instead of symbols on the cards, little hearts would have dotted the Is.

I’d never tracked the source of a pivot before. Would it sound different from the rest of the Echo? Louder? Would it be unstable, like a break? Easy enough to find out, and I set off for the science wing, taking the stairs two at a time.

“Del!” Eliot called behind me.

“Glad you could make it.”

“It’s dangerous to Walk by yourself,” he said when he’d caught up. “What if something goes wrong?”

“You worry too much.” Eliot’s preference for navigation over Walking wasn’t only because his brain was wired like a supercomputer. His mom ran one of the Consort homes for elderly Walkers, the kind my mom wanted to send Monty to. Eliot had grown up witnessing the toll our abilities took. I looped my arm through his. “Besides, you’re looking out for me. Safest Walk in the world.”

“Why do I let you talk me into this?” he asked as we set off. He twisted to avoid the streams of people filling the hallway.

“Because I am irresistible. Who’s giving a chem test today?”

“Doc Reese,” he said. “I heard someone talking about it in lit this morning.”

“Time to see Doc Reese.” The bell rang, and we flinched.

“We’ll be late for music. Again. I hate being late.”

“Then we’d better hurry.” We dashed through the halls, until he pulled on my elbow so hard I staggered.

“Here. This is longer than eight minutes.”

People filed past us, and I wove around them, trying to avoid the contact that would draw their attention. Inside the classroom kids were settling into place, pulling out pencils, calculators, and . . . yep. Note cards.

Doc Reese stood behind the table at the head of the room, sporting his usual lab coat and bow tie. His bony hands clutched a thick sheaf of papers. “The sooner you’re seated, the sooner we’ll start,” he said, his voice doleful.

The cards vibrated in my hand, gaining strength as the frequency crescendoed. I peered through the narrow window, studying the back of every girl in the room. They were perched on their lab stools like brightly colored birds, arranging pencils and reviewing notes—except for one girl, crouched on the floor, frantically emptying her backpack. “Bingo. Third row, left side.”

Eliot checked the map again. “Great. Time’s up.”

I shook off his arm. “What if I gave her back the cards? What would happen?”

“We’d be even more tardy.”

“Five minutes,” I said. “Think of it as an experiment.”

He scowled, but didn’t stop me.

The room smelled of sulfur and nerves. I eased past the kids lined up at the pencil sharpener, dropping the cards a foot away from the girl’s backpack. Her pitch grew sharper as I waited for her to notice.

Panic must have blinded her. She dug through her bag with staccato movements. Her sniffles were audible behind her curtain of light brown hair. The second bell sounded, and Eliot waved wildly from the doorway, pointing to his watch.

So much for limited interference. I touched her shoulder. “You dropped something.”

She lifted her head, red-rimmed eyes startled. I pointed to the note cards, and she fell on them with a squeal. “Oh my God! Thank you!”

“No problem,” I said, but she was too focused on the cards to respond.

Doc Reese, on the other hand, spotted me. “Can I help you?”

“Just leaving,” I said, backing out the door.

“The pitch is changing,” Eliot said. Onscreen, the dot of light was folding in on itself like a collapsing star.

“Because of the note cards?”

“Must be. It started right after you handed them over. I didn’t think it was possible to alter an Echo’s frequency.”

“Me neither. It’s kind of cool,” I said as we headed down the corridor, my short legs struggling to keep up with his lanky ones. A strange quiver ran through the air.

“Did you hear that?” I asked, my steps slowing.

Eliot tapped the screen. “It’s reverting to the Key World frequency.”

I stopped. “Do not tell me we created a second Key World.”

“You’re good, Del. But not that good.” He scanned the hallway we’d come from. The lockers blurred and snapped back into focus, like adjusting a camera. The lines on Eliot’s forehead deepened, and fear sent a wave of dizziness crashing over me.

“Did I cleave it?”

“No,” he muttered. “It think it’s a transposition.”

Choices create worlds, but not every world is sustainable. When you decide between strawberry and blueberry yogurt for breakfast, odds are good your morning will play out exactly the same way. When that happens, the multiverse autocorrects, absorbing the new branch into the older, more established one. The same thing happened when Walkers made a choice—without an Echo to sustain the pivot, the branch reabsorbed into the Key World almost immediately. The effect was called transposition.

The thing is, consequences are like people: hard to predict and harder to change. If the blueberry yogurt is expired, you could end up with food poisoning and spend three days in the hospital instead of at school—a big difference rooted in a small choice. We never knew which worlds would transpose and which would form significant Echoes, but since transpositions were both common and harmless, we barely touched on them in class.

Now that I was inside one, they didn’t feel harmless. Across the hallway, the bio lab doubled and merged, the Key World room overtaking the Echo one.

“This is not good,” Eliot said, eyes shifting between the map and the wavering corridor. “Since when can we cause transpositions?”

“Hell if I know,” I said, and pulled him toward the stairs. “What happens if we don’t get back before the Echo is absorbed?”

“The frequency will carry us back into the Key World wherever we’re standing at the time. Like we’re surfing into shore. Could be a rough landing, though.”

It couldn’t be any worse than escaping from a cleaving. “Won’t people notice if we appear out of thin air?”

“Nope. It’s a continuous transfer. Their Echoes see our impressions before the transposition and the Originals see us after. Once they’ve combined, they think we’ve been there the whole time.”

It made sense. People ignored what they couldn’t explain. It was more comfortable that way, and Walkers exploited that weakness all the time.

“Then why are we running?” I asked, and stopped short.

“We’re late for music. Eight minutes, you said. This is more like fifteen.”

“Maybe not,” I said. “If we can sneak into class before the transposition’s done, Powell will never notice we were late.”

Eliot gestured toward the rapidly stabilizing staircase. “The transposition’s nearly finished. She’ll catch us.”

“Pessimist,” I said, and took off again, headed for the music wing.

The curving wall of cement block pulsed as the frequencies melded, the tile beneath my feet shifting. I lost my footing, and the transposition caught up with us, sending Eliot careening into me. My shoulder slammed into the wall, and I swore loudly.

When I looked up, Ms. Powell was standing outside the classroom, her expression puzzled. Confusion was replaced by exasperation as the Key World’s signal overtook the Echo’s, the sound locking into place.

She’d seen us. The transposition was complete, and we were too late.

“Sorry,” Eliot wheezed as we struggled past her. “Really sorry.”

Simon glanced back for an instant, but didn’t say anything before returning his attention to Bree. I studied the nape of his neck, the breadth of his shoulders under the thin gray T-shirt—and took a few deep breaths, trying to recover from my sprint. The crisp scent of cotton and citrus rose off his skin, so different from his Echo.

“Eliot, Del,” said Powell, as we flopped into our seats, “glad you two made it.”

CHAPTER FOURTEEN

The ability to Walk is hereditary. Recent advancements in genetics and neurology have revealed a mutation on chromosome 8q24.21, corresponding to hyper-development of the primary auditory cortex. This mutation enables Walkers to detect and manipulate matter on a quantum level. Other characteristics frequently tied to this chromosome include perfect pitch and a predisposition for early-onset dementia.

—Chapter Four, “Physiology,”

Principles and Practices of Cleaving, Year Five

MS. POWELL LEANED against the podium like a lounge singer on a piano. “Since everyone’s finally here, get together with your partner and start planning. This is your last big project before the semester exam, so you’ve got a solid month to write and rehearse your composition. I’ll give you the whole period today, but the bulk of the work should be done on your own time.”

My head snapped up. Time with Simon. The real Simon, the one I couldn’t form proper sentences around. Anticipation and anxiety weren’t so different, not under the skin, where my heart stuttered and my blood skipped.

While my classmates rearranged their desks to meet with their partners, I sat catching my breath, unsure how to approach Simon.

As it turned out, there was no need to figure out an approach. He spun around in his chair, his legs knocking into mine and staying there. It was the kind of casual, flirtatious move I’d seen him use a million times with a million other girls. Now that I was on the receiving end, it felt anything but casual.

“So. Delancey.”

He’d never said my name before. Not ever, in this world, and not my full name in any world, and the way he said it—slow and thoughtful, like he was considering the way each syllable felt in his mouth—stole my breath anew.

“Simon,” I said, trying to mimic his tone, trying to shake off the weirdness, trying not to gape. “And it’s Del.”

“Del. You’re good at this stuff, aren’t you?” He held up the packet Ms. Powell had given us, full of rubrics and instructions and blank staff paper. “It’s your thing.”

“My thing?”

“Aren’t you some kind of music prodigy? You always know the answer to Powell’s trivia. Plus, she’s made you play the violin for us a bunch of times. Piano, too.”

I stared at my hands, my fingertips roughened from hours practicing. This is what he’d noticed about me? My freakish musical ability? “My family’s big into music.”

Not only my family. All Walkers had perfect pitch. While our love of music wasn’t genetic, I’d never met one who didn’t play at least three instruments.

“What about you?” I asked, wanting to shift his attention. His Echo had watched the band with the focus of a musician. How did his Original compare? “Didn’t you used to play the drums?”

“In sixth grade, sure. A bunch of us thought we’d start a band in Matt Lancaster’s garage.” He shook his head. “I can’t believe you remember that.”

I remembered more than his ridiculous band. Sixth grade was the year his mom found out she had cancer, and the whole community pulled together—throwing car washes and bake sales, raffles and walkathons. Even my mom had helped out, dropping off casseroles and containers of soup. Mrs. Lane had recovered eventually, and every mother in town had wanted to adopt Simon. Five years later, they still did.

“My mom tried me on a bunch of instruments, but it was a total disaster. She says I couldn’t carry a tune in a paper bag.” His smile quirked and his voice dropped. “Be gentle with me.”

“Composition isn’t that hard, I promise.” I cringed at the eagerness in my voice. I’d been brave enough to flirt back when I’d met him in Doughnut World; why couldn’t I do the same here?

Because bravery comes easily when there’s no cost to it. Anything was possible in Echoes; if I didn’t like one world, another, better one was a few short steps away. I could kiss Doughnut Simon without fear of consequences. He wasn’t real, no matter how hard he’d kissed me. It was heat and spark, with no chance of being burned.

I liked who I’d been last night, and I tried to recall her now, saying, “Do girls usually fall for the whole ‘charming your way out of work’ routine?”

A few feet away, Bree watched us through narrowed eyes, ignoring Eliot’s attempts to catch her attention.

“Depends on the girl,” he said. “Not you, I’m guessing.”

“Not even close.”

He studied me, tapping his pen on the desk. “We’ve had classes together before, haven’t we?”

Freshman biology. Geometry and civics sophomore year. This year it was American history and music theory. But if he couldn’t remember, I wasn’t going to point it out. “Probably.”

“That explains it.”

“Why I’m immune to your charm?”

“Why you look familiar.” He pretended to look insulted. “And who says you’re immune? You’re smiling.”

“I’m not. . . .”

“Oh, yeah. Right . . . here.” His thumb touched the corner of my mouth, the slightest pressure, his fingers curling under my chin, the Key World’s frequency rising around us.

I didn’t throw myself onto his lap, or anything quite so obvious. But I felt obvious. Clumsy and naive, definitely not the version of myself I wanted to be around him. The charge running through me at his touch must have been written across my face.

He was supposed to look smug. Everything I knew about Simon Lane prepared me for his eyes to light up with triumph, like the scoreboard after a three-pointer. Instead, he looked confused.

“Making progress?” inquired Ms. Powell, wandering past.

Simon let go of me, shook his head as if to clear it. “Excellent progress, ma’am.”

For once, I kept my mouth shut.

CHAPTER FIFTEEN

Identifying the choice that triggered an Echo is exceedingly difficult. Historical analysis can be used with some degree of success, but unless the pivot formation is witnessed in real time, theories about why an Echo formed cannot be proven.

—Chapter One, “Structure and Formation,”

Principles and Practices of Cleaving, Year Five

ARE YOU SURE you can handle him?” Eliot asked once class was over.

A few feet ahead of us, Bree and Simon were walking together, his dark head bent over her fair one. It was as if our strange, electric moment was even more of an aberration than the time I’d stolen with his Echo.

“Absolutely,” I said, forcing a lightness I didn’t feel. “It can’t be any worse than working with Bree. That looked super fun, by the way.”

Eliot grimaced. “I never thought I’d say this, but I agree with her. Powell should let us switch.”

He doesn’t even know your name, Bree had said. “It’s good for Bree to experience disappointment. Builds character.”

Eliot transferred his frown to me. “Don’t tell me you want to work with him.”

Simon and Bree stopped outside the history room. After a short conversation—one where Bree stroked his arm and tossed her hair and batted her eyelashes, as subtle as a two-by-four upside the head—he ducked inside.

The moment he was out of sight, her friends swooped in with an audible squeal. “Did you ask him?” one asked in a mock-whisper.

Bree’s smile slid away. “Maybe tomorrow.” She caught my eye before they disappeared down the hall, the glare so unmistakable even Eliot recoiled.

“You might want to reconsider going to Mrs. Gregory’s class today.”

“I can handle Bree.” Open hostility was easy to deal with. Simon’s unpredictable, unexpected tension was more dangerous. “Give me your phone.”

“Why?”

“To order a pizza,” I said. “Why do you think? We have a sub in history again. I need something to do while she shows the movie.”

“You could try watching the movie for once.”

“Why bother?” I slipped a hand into his jacket pocket and tugged the phone out. “You’re a sweetheart.”

“I’m a pushover. Promise you won’t get caught.”

I blew him a kiss. “I never do.”

The movie was as mind-numbing as I’d predicted. Five minutes after the opening credits, the sub was playing computer solitaire and the class was evenly divided between napping and texting. Simon, legs sprawled in front of him and chin propped on fist, was in the first group.

I was playing with Eliot’s new toy.

I was not thinking about Simon, and the feel of his thumb against my mouth. Or Simon in the rain. Or in the park. I was not thinking about any of those things when I zoomed in on the music room, examining the pivots that had sprung up during class.

Beginnings meant branches. Nobody in history was making decisions except the sub, and the display showed a dim, nearly lifeless room. But in music, each group had made a bunch of choices as we planned our projects—when to meet, how to divide the work, what instruments to use. The screen should have looked like a Christmas tree.

Instead, there was a single, overwhelming glow, growing steadily brighter as the edges of the circle spread out, one all-encompassing pivot.

And then the map crashed.

I tapped the screen and clicked the buttons, but nothing worked. I didn’t know much about Eliot’s gadgets, but whenever they glitched, he’d ask me a million techie questions. “What were you doing when the error occurred? What did the screen say? What settings were you using?”

He’d ask a million more now that I’d broken his baby. I’d be doing him a favor if I checked out the music room in person.

I approached the sub. “Bathroom pass?”

She waved at the door, too intent on her cards to worry about me. A few minutes later I was back in the music wing, phone rebooted and working again. Everything looked normal. Everything sounded normal—freshman band squawking away in one room while swing choir rehearsed in another—the Key World strong and sure. The map shone brightly as I peered into Powell’s empty classroom, and when I opened the door, I caught the buzz of a solitary pivot.

A good-size one, I saw, big enough that the fluorescent lights seemed to catch on the edges of the rift, leaving shadows in midair. It was centered directly over Simon’s seat. I thought back over our conversation. He’d noticed me, but that wasn’t enough. A frequency as jarring as this one came from a deliberate, significant choice. What was it?

He’d touched me.

I’d thought it was his usual routine—heavy on the flirting, light on substance—but the quavering air above his desk suggested otherwise. If he’d touched me in the Key World, what had he done differently in the Echo?

According to Eliot’s map, the pivot was stable enough to visit. I slipped the phone into the pocket of my sweater, found the star I’d been folding in class, and stepped through, holding my breath like I was diving into deep water.

The room I surfaced in stood empty. Whatever choice Simon made wasn’t visible, but the pitch was unexpectedly loud. If I was going to figure out what had changed, I’d need to do it fast.

My best shot at pinpointing the change was to find his Echo. I dropped the star on the piano and headed to history.

No one in Echo history noticed my entrance. The movie played on as I slid into the seat next to his, deliberately jostling him awake. His dissonance sent a shock through me, but he smiled, sheepish and sleepy lidded. “Del. What’s up?”

His whisper found its way under my skin. I squashed the urge to lean in closer, to recreate our connection. Hooking up with Simon was a bad idea in any world, but particularly now, when I was pressed for time and looking for answers.

Certainty is a luxury, whether you’re dealing with the multiverse or a human being. We’re never 100 percent sure what creates a pivot unless we see it form. We never fully understand another person, even those we’re closest to. Best guesses and backtracking were imperfect, incomplete pictures, whether you’re dealing with branches or boys.

I tried to be logical: In this world, Simon hadn’t touched me. We hadn’t had that strange, deliciously tense moment. Powell hadn’t interrupted us. But what was the result?

“Tell me again when we’re meeting?” I rubbed at the back of my neck, trying to quell the gathering tension.

“You forgot?” The movie cast shadows across his face. “Sunday. At the library.”

Same as the Key World. He looked identical, but the pitch was definitely different. I gritted my teeth. I should be able to see such a significant change.

Unless I was looking at the wrong person. “So . . . you and Bree?”

He sat up, annoyance tightening his features. “Where’d you hear that?”

“Around,” I said vaguely. “You two are back together, huh?”

“Taking her to a party doesn’t mean we’re together. I haven’t even told her yes.”

She’d asked him out. I could trace the chain of events like dominoes falling. In our world, Bree had seen our interaction and decided to hold off. In this one, he hadn’t touched me, and she’d had no reason to wait. His answer would trigger a second pivot, and her response would create a third. Eliot’s map should have shown an entire galaxy of Echoes; instead I’d seen a supernova. It didn’t add up.

“Anything else exciting happen after class? Anything weird?”

He tapped his pencil on one lean, denim-clad leg. “A girl I just met started asking me a bunch of questions. Does that count?”

“Ah. Weird girl.” I was glad it was dark. The sub looked up, and Simon pretended to watch the video until she’d gone back to her game.

“The questions were weird.”

“Not the girl?”

“Early days.” His gaze swept over me, but I couldn’t stay to investigate any longer. Class was nearly over, and the last thing I needed was another detention.

“Gotta go.” I stood, feeling unsteady.

“You’re going to walk out?”

“Trust me,” I said. “Nobody’s going to notice.”

I made it back moments before the lights came on. The sub blinked at the sight of me, and I waved cheerfully.

Before I could escape, a hand clamped on my arm.

“And where did you sneak off to?” Simon said as we filed out, bending down to murmur the words. “Meet up with your boyfriend?”

“I don’t have a boyfriend.”

He brushed my hair away from my neck. “Where’d you get the hickey?”

“The . . . oh.” I covered my throat with my hand, conscious of how the red welt must look. “It’s from my violin.”

“Mmn-hmn,” he said. “You’re telling me you and the skinny guy aren’t together? Friends with benefits?”

“Eliot’s my best friend.” The edge in my voice was audible despite the noisy hallway. “That’s it. Why do you care, anyway?”

“I’m trying to get a feel for you.”

Someone slammed into me. Simon placed a steadying hand on my hip, leaving it there a beat longer than necessary.

“A feel for me?” I said, trying to sound skeptical instead of scattered.

“We’re partners now. And when my partner cuts class, I get curious. I’ll figure it out eventually, Del.”

“Don’t bet on it.”

CHAPTER SIXTEEN

Once a cleaving is completed, the First Chair must submit a formal report to the Consort Archive. It is traditional for Walkers to maintain a journal of their personal Walks as well, as a reference for future generations.

—Chapter Three, “Echo Properties and Protocols,”

Principles and Practices of Cleaving, Year Five

UP,” SAID ADDIE the next morning.

“Bite me.” I pulled the covers over my head. She yanked them back, and I shrieked at the rush of cold air. “What is your problem?”

“It’s practically noon,” she said.

I squinted at my clock. “It’s ten thirty. On a Saturday.”

“Suspended does not mean vacation. If you were going to training, you would have left hours ago.”

“But I’m not, thanks to you. Get out.”

“Mom said you can either clean the bathrooms or work with me. Your choice.”

“You are such a bitch.” I sat up and shoved tangles of hair out of my eyes.

“I’ll be in the kitchen,” she said over her shoulder. “Fifteen minutes, or you’re scrubbing toilets.”

I stumbled out of bed, shuffled downstairs for a shower, and made it into the kitchen thirty seconds ahead of Addie’s deadline. “Where are Mom and Dad?”

“Some meeting downtown with the new teams. They’ll be back by dinner.” She waved a hand at my wet hair. “Don’t drip on the table.”

I ignored her, heading straight for the coffeemaker. The caffeine didn’t improve my mood any, and neither did the piles of textbooks on the kitchen island, which I deliberately dripped on.

“You haven’t been keeping up with your reading,” she said with a frown.

“I read journals. That’s plenty.” I’d studied Monty’s journals since I was a kid, deciphering the cramped, messy writing, thrilling at the near escapes and crazy stories. Textbooks were dry and lifeless in comparison.

“You need to understand the theories before putting them into practice,” she replied, pushing the pile of books across the table.

I pushed them back. “Or I could, you know, practice. Theories didn’t help the other day.”

“If you’d had a better grip on the basics, you wouldn’t have cleaved that Echo to begin with,” she said.

“I got us out,” I snapped, my temper breaking free. “Not your stupid books. That’s what burns you, isn’t it? People won’t shut up about how perfect you are, how you follow every rule. But it’s not because you’re smart. It’s because you don’t have the chops, and I do, and now everyone knows it.”

“Screw you,” she hissed. “You think you’re so special? You’re going to fail your licensing exam. When you do, the Consort—and the rest of the world—will finally see you’re more trouble than you’re worth. And I. Can’t. Wait.”

I was halfway across the room, arm cocked for a punch, when Monty shuffled in.

“Man can’t play a tune with you two shouting. Bet they can hear you five worlds away.”

“She started it,” I said, as Addie complained about how disrespectful I was.

“Girls!” he boomed. We fell silent. “Are there cookies left?”

I could see Addie counting to ten in her head. “We ran out,” she said. “But it’s Saturday. Mom’ll bake tonight.”

“Bake on Saturday. Your mother used to do that.” His face brightened. “She’ll come home and make apple cake and we’ll play a hand of rummy. She cheats at rummy, Rose does. I don’t mind, really, but it’s better not to tell her.”

He’d slipped again, mistaking Addie for my mom.

“Grandpa, it’s Addison. Remember me?” She touched his arm, trying to jog his memory.

He blinked at her, owl-like. “I’m old, Addie-girl, not stupid.”

Faster than I’d thought possible, he crossed the room to the coatrack and grabbed his battered porkpie hat. “Walk with me, girls. It’s a beautiful day, and I haven’t lost all my moves.”

Addie lifted up a textbook. “Del’s supposed to be studying.”

“She knows enough to get where she’s going.” When Addie didn’t budge, he added, “Let’s show her how it’s done.”

Addie sighed and scooped up a pile of papers while I slung my bag over my shoulder. Monty winked at me and did a soft-shoe routine out the door.

Twenty minutes later we were surveying the football field. The sky was a pure, clear blue, wisps of clouds drifting across. The air was crisp enough to make me glad I’d worn my coat. Addie consulted her paper map, checking it against the deserted parking lot. “I was planning this for next weekend, but I suppose we could try it today.”

I couldn’t imagine thinking so far ahead, but knowing Addie, she’d already worked up lesson plans for my entire suspension. Still holding the map, she drew a slim black rectangle out of her purse. Not a cell phone, but it could pass for one if you didn’t look too closely. Her fingers flew over the keys as she punched in a string of numbers.

A generator: Input the specific resonance of an Echo and it would play the frequency for you. More reliable than memory, they were for licensed Walkers only. I wouldn’t get one of my own until—or unless—I became an apprentice.

“Don’t go without us,” she warned, and pressed a final button. The generator wheezed like an accordion.

I found the matching pivot almost immediately. “Concession stand,” I said, and at Monty’s nod, led the way.

The world looked similar to ours, but I barely had time to note the differences, because Addie played another pitch. “Go.”

“This is kindergarten stuff,” I complained. If this was supposed to be next week’s work, she’d planned for a glacial pace. I’d die of boredom—and be months behind for the exam. That was probably her intention. Monty nonchalantly dropped a button while her back was turned.

“Then it shouldn’t be a problem,” she said sweetly. “Go.”

I checked my phone, now running Eliot’s map software. The light of the pivot was bright but steady. Safe to go. I found the new frequency and Walked through again, feeling the air flex and settle around me.

“Told you,” I said. “Kindergarten.”

“Again,” said Addie, and picked a new frequency.

By the fifth crossing I’d lost patience. We’d reached the center of town. In each world, the dissonance increased, and so did my frustration. “This is stupid. Can we do something else?”

Monty nudged her. “Wouldn’t hurt to push her a bit. You can tell her if she’s doing it wrong.”

“Oh, fine.” She waved an arm at the surrounding buildings, the pedestrians enjoying a Saturday-morning stroll. “Map it.”

I blinked. “The entire Echo?”

“Too much?” she replied. “You’re such an expert, prove it. We’ve got two hours left. Mark as many pivots and breaks as you can. We’ll compare it to the most recent map when we get home, and you can write up an analysis of the changes.”

If her plan was death by dullness, it was working. I opened my mouth to complain, but Monty interrupted.

“Start there,” he said, and pointed to a coffee shop across the street. “I need a snack.”

A few minutes later Monty was plowing through a blondie the size of a deck of cards while Addie sipped a cup of tea. I slouched in an overstuffed chair on the other side of the room, a notebook in my lap, the café’s floor plan sketched out. I’d tried to use Eliot’s software, but Addie was watching me too closely. I’d have to do this the old-fashioned way.

I ignored the indie-folk blaring on the radio and listened. Snatches of conversation floated around me: plans for the rest of the afternoon, gossip, quarrels, friends doling out advice to one another. My pencil flew over the paper, drawing an X for each pivot that formed. I couldn’t get a clear read on their strength. If Addie wanted that kind of detail, she’d have to let me Walk more.

The highest concentration of pivots was near the counter, not only at the register, where people placed their orders, but along the open space where people lined up to study the chalkboard menu. Some of the rifts formed and dissolved again with a drone like a mosquito. Transpositions, probably, and I marked them with a small wavy line.

Eliot had been stumped by yesterday’s transposition. By returning the girl’s note cards, we’d altered the frequency of an entire Echo. But Walkers didn’t change Echoes; we cleaved them. Neither my parents nor my teachers had ever suggested another possibility. I wondered why not.

A group of chattering girls, identical in their suede boots and fleece jackets, shopping bags weighing down their arms, approached the register. I didn’t recognize any of them, but something about them—their airy confidence, maybe, or the way they expected everyone else to make way for them—reminded me of Bree.

One of the girls, a dishwater blonde with heavily glossed lips, asked, “Is Soren working today?”

The woman behind the counter, who sported an impressive number of piercings and perfectly applied kohl liner, rolled her eyes. “Not for another hour.”

“Oh,” the girl said, crestfallen. The air around her stirred faintly, the beginning of a break. “We could wait, right? Surprise him?”

“Go for it,” the barista said in a tone suggesting Soren would not, in fact, be surprised by the sight of four girls giggling into their skinny caramel lattes.

The café was nearly full—all that was left was a low table in front, with a couch on one side and two chairs on the other. It was the perfect place to see and be seen, and the only spot where the four girls would fit.

As they waited for their drinks, Monty ambled over, handing me a cappuccino. “Having fun?”

“Not particularly.”

He gave me a conspirator’s wink. “Would you like to?”

“Most definitely.”

He tipped his head toward the girls hovering at the counter. “Hard to concentrate with their gabbing, isn’t it? Bet you could convince them to leave.”

“They’re too stable,” I said. “The break around Lip Gloss Girl is tiny. Addie would kill me if I interfered.”

Addie and Monty had made direct contact so the cashier would notice them and take their order, but I’d been sitting undetected in my chair for thirty minutes. I wondered if I could sneak a nap.

“Influence, not interference,” he chided. “Oldest trick in the book.”

Before I could stop him, he scooped up my backpack and dumped it on one of the empty chairs.

The ringleader, a tall brunette, had been eyeing the table. She blinked and turned to the others. “Why don’t they have more seats?” she complained. “We’re going to have to squish in.”

Monty’s plan became clear. Swiftly, I tossed my coat on the other chair and stretched out on the couch, feet on the cushions, moments before the girls collected their drinks. They stopped a few feet away, confused. In the Key World, I would have been on the receiving end of haughty looks and barbed comments, maybe even a veiled threat.

The Echo clique wouldn’t remember any details about me. They knew their plans to sit by the window had been thwarted, but if you asked them to explain why, the best they’d be able to come up with was, “Someone took our seats.” I was insubstantial and utterly forgettable, but I could change their path.

“Let’s check out the bookstore instead. Maybe that hot guy is working the customer service desk.” The brunette tossed her hair and headed for the door, a pivot forming in her wake. The others trailed silently after her, and the break around Lip Gloss Girl steadied.

Monty thumped down on the couch next to me with a grunt and perused my map. I dumped a bunch of sugar into my drink and folded a star from the empty packets, just to pass the time.

“I give up,” I said eventually. “What was that? Her break fixed itself?”

“It’s called tuning,” Monty said as Addie joined us. “Addie’s seen it before, haven’t you?”

“I have,” she said, dropping my backpack on the floor and sitting down. “It’s a weird side effect of Walking—when we interfere with a break, their pitch will sometimes stabilize.”

“You can bring them back in tune,” Monty said cheerfully. “Neat trick, isn’t it?”

“Sure, if it doesn’t make things worse,” Addie replied. “You shouldn’t have encouraged her, Grandpa.”

I thought back to the note cards. “Can you fix entire Echoes?”

“Theoretically, yes. But there’s no point. It’s more efficient to cleave Echoes than fix them. Safer, too.” Addie waved her hand. “Have you finished?”

“Almost. There’s one behind the door, I think.”

In the back of the café was a door with an EMPLOYEES ONLY sign.

“Go check it out,” she said. “And don’t try to fix it. Get the reading, and we’ll leave.”

I crossed the room, trying to connect Addie’s explanation of tuning and the transposition from yesterday. Was it possible I’d tuned the Echo so well it had transposed? Was that illegal? Considering I’d violated my suspension the instant I crossed over, asking Addie was not an option.

The door was locked. I pressed my ear against the wood, trying to hear the break on the other side. The frequency was fluctuating wildly, and I couldn’t get a good sense of its strength.

“Can’t get in,” I said, returning to the couch. I drew a question mark on the map and Addie scowled. She’d never been a fan of unanswered questions.

“Get the key from the cashier,” she replied.

“How am I going to do that without touching her?” I shot back. “You wanted me to map the break, and I did. End of story.”

“Not end of story,” she replied. “Pretend for a minute that hell freezes over, and you actually get your license. Cleavers initiate their cuts as close to the breaks as possible, to keep them under control. You’d need a way into that room.”

“I’ve got a trick for that, too,” said Monty. He slapped his knees and hefted himself off the couch. “Time for more fun.”

“This isn’t supposed to be fun,” Addie replied.

“Trust me, it isn’t,” I said under my breath.

“No need to squabble,” said Monty. “Del’s supposed to be learning, so we’ll visit the school.”

“Basketball game tonight?” Addie asked. The statue of George Washington outside the front door was dressed in a fire-engine red uniform. In the Key World, our colors were blue and white, but the tradition was the same, apparently.

“Like I would know?”

Monty headed for a side door, and I chased after him. “They lock it up on weekends. Only the custodians and teachers have keys.”

“Haven’t bothered with a key since I met Rose,” he huffed, and pulled out his wallet. “Watch and learn.”

“Lock picks?” Addie said. Her ponytail whipped back and forth frantically. “Grandpa, you can’t break into the school.”

“Good point.” He sat back on his haunches. “You’ll never learn if you don’t try it yourselves. Del?”

I took the slender metal hook he handed me.

Addie snatched it out of my hand. “No. This is against the law.”

Monty tsked. “Whose law? Whose jurisdiction are we under, Addison?”

She struggled to answer, but finally said, “The Consort’s.”

“Indeed. Any crime committed in service to the Key World is no crime at all. That is what they teach you, isn’t it? How they justify what they do?” His voice shook, but his hands were steady as he maneuvered the picks.

A minute later the door swung open.

“In we go,” said Monty. I helped him up, his arm knobbly and fragile underneath my grip. Despite his mischief and stubbornness, he was old. I forgot that, sometimes. Forgot the toll his Walks had taken. “We haven’t got the whole day. And I need another snack.”

The main building was shaped like a rectangle, and we’d entered at one of the corners, the two hallways on either side of us forming an L. Monty’s words reverberated down the corridor, past darkened classrooms and banks of lockers.

And every single door had a lock.

My fingertips tingled, the same as before every Walk—so much possibility. So many things to see, even if it was the same school I went to every day.

I’d had freshman geography in the first room I came to. Here it was a German classroom—a flag draped in front of the windows, maps lining the walls, homework assignments and verb conjugations written on the board. Nothing interesting, except that the knob wouldn’t turn under my hand. I was about to ask Monty for his picks when Addie recovered her wits.

“That’s it,” she said, taking his arm. “We are going home. Right now. Someone has to be the adult here.”

He tugged away from her, surprisingly forceful. “That’s me,” he snapped. “We’re not leaving until the two of you learn some real skills. You can’t rely on the Consort to teach you what you need. They’ll only teach you what they need. It’s not the same thing.”

I shot Addie a triumphant look, and Monty rounded on me. “Instinct isn’t enough either. You want to outwit everyone else, you need to practice.”

He slapped his hands together and surveyed the hallway. “Let’s get started.”

Monty’s lesson took longer than we thought—but even though we arrived home after dark, dazed and headachy from so much exposure to bad frequencies, my parents were nowhere to be found. Addie checked her voice mail while I texted Eliot to see if he was home from training.

“They’ll be home late,” Addie announced. “There’s a casserole in the fridge.”

“No apple cake?” Monty said mournfully.

“Mom will bake tomorrow,” Addie said, and dished up a giant bowl of rocky road to hold him over until we ate. Grumbling, he took it up to his room. When he’d gone, Addie blew out a long, slow breath. “Cocoa?”

“With extra Fluff,” I said, pulling a squat white jar out of the pantry.

Addie poured milk in a saucepan, eyes troubled. “We should tell Mom.”

“That we spent today breaking and entering? She’d freak out.”

“She should.”

“You’re the one who says Echoes aren’t real, so what’s the harm? If they think we can’t handle Monty, they’ll put him in a home.”

She was quiet as the milk heated, then stirred in cocoa and sugar. When the mixture was steaming, she finally spoke. “This isn’t the first time he’s taught you something shady, is it?”

I got down mugs and spooned in big globs of Marshmallow Fluff. “Not shady. Just . . . extra techniques. Like when I stole Simon’s wallet.”

“Do you really think they’re helpful?”

Mostly, Monty’s tricks were fun. A way to show off, even if no one noticed. But I’d used them enough to know they could have a big impact, made bigger by the fact that people didn’t expect them.

“It’s another thing to add to the toolbox,” I said, thinking of the leather case full of picks sitting in my bag. Monty had given them to me while Addie was distracted, insisting I would get more use out of them. “You don’t have to use it, but it’s nice to have the option.”

She filled the mugs, and the Marshmallow Fluff bobbed to the surface like a buoy. “It feels . . . wrong.”

“It’s no different from a screwdriver. Right or wrong depends on how you use it.” Learning to pick locks seemed minor compared to Monty’s lesson in tuning. No one had ever told me we could repair Echoes. What if I could have prevented Park World’s cleaving? Saved Simon and Iggy and the rest? I pushed the mug of cocoa away, feeling ill.

“Maybe.” She stared into her cup, glancing up when someone knocked on the front door. “Is that Eliot?”

Eliot used the back door—and he never bothered to knock. For a fleeting second I hoped it was Simon, but that seemed impossible. The knock sounded again. I opened the door and stepped back quickly, as if I’d found a rattlesnake on my doorstep.

“Hello, Delancey,” said Councilman Lattimer. “I’d like to come in.”

CHAPTER SEVENTEEN

I WOULD NEVER get used to the way the Consort didn’t ask questions. They made statements, a weird formality designed to reduce the pivots around them. Pointless, considering that Walker-created pivots couldn’t sustain themselves, but they clung to the tradition.

“My parents are out,” I said as Councilman Lattimer crossed the threshold. “Working.”

“I’m aware. I’m here for an update on your progress, per your sentence.”

“Shouldn’t that be Shaw’s job?”

He peered into the living room, with its jumble of instruments. “I assure you I’m qualified.”

Addie sloshed cocoa everywhere at the sight of a Consort member strolling into our kitchen.

“Not Eliot,” I said.

“Councilman!” She shot out of her seat. “We’re—I’m—how can we help you?”

“I’m here for Delancey’s progress report. Since your parents have placed you in charge, I thought it simpler to get the information directly.”

He gave her an expectant look, as if his patience was already wearing thin.

“I haven’t written a formal report yet,” Addie hedged, “but she did well. We spent today reviewing navigation and cartography, and discussed strategies for directly analyzing breaks.”

Impressive. It was a much better spin than, “We hung out at a coffee shop and burglarized a school.”

“I trust you’ve limited her Walks only to supervised training?”

“Yes, sir. We’ve monitored her very closely.”

“We. You and your grandfather, I presume.” He looked up at the ceiling, where Monty’s shuffling gait was audible. “Are you certain neither of them slipped away unnoticed?”

A direct question from a Consort member was virtually unheard of. He must have been genuinely curious, and his curiosity fueled my own. Was he here to check up on me, or Monty?

Addie was too caught up in the implication she’d been lax in watching me to notice his slip. “The Consort’s expectations were very clear. I had eyes on Del the whole time.”

I did my best to look obedient and remorseful.

“It’s important that you supervise your grandfather as closely as you do your sister, lest he wander off. Also, you should be aware his methodology often conflicts with standard practice.”

“He’s got years of experience,” I blurted. “Why not learn from that?”

He turned on me, predatory as a hawk. “The lessons you can take from him are cautionary at best. You’d do better to learn from your sister. We need more Walkers like her.”

Addie straightened, her posture more impeccable than usual as he turned to her.

“We appreciate your willingness to help, Addison. Once your apprenticeship is concluded—and assuming your work with Delancey is successful—the Consort will make sure you’re given a position worthy of your abilities.”

On the surface the words sounded complimentary. But the underlying message had an ominous note: If I failed, I wouldn’t be the only one punished.

“Yes, sir,” she said, eyes wide. She’d heard it too. “Thank you.”

“Excellent. Send me your written reports, as well as your plans for the upcoming week. I’ll continue to check in personally.”

“That’s not necessary, sir. Del’s caused you enough trouble.”

“No trouble at all.” His smile fell several degrees short of warm. “It’s the least I can do for the granddaughters of my old friend. Especially considering that he’s in no condition to do it himself.”

Before Addie could manage another timid “Yes, sir,” he was gone.

“Well, that wasn’t creepy.” I threw the dead bolt and headed to the kitchen. “Why does the Consort care so much about me? I figured they’d hand me off to Shaw again, especially since they’re busy with Mom and Dad’s special project.”

Addie stared into her mug, lost in thought. “Grandpa was a big deal when he was a Cleaver. A lot of people thought he would be selected for the Consort, before Grandma disappeared. Maybe they think they’re doing him a favor.”

“Some favor,” I said. “Monty and Lattimer can’t stand each other.”

“No, they can’t. But he was important. Mom and Dad are important. They can’t publicly show favoritism, but behind the scenes . . .” She shrugged. “Regardless, Lattimer’s right about Monty being a bad influence. He keeps losing time, Del. He’s slipping.”

The cocoa coated my tongue, making it thick and clumsy. “Only a little. When it’s important, he focuses.”

“It’s what he deems important that worries me,” she replied.

My whole life, Monty had encouraged me to stretch myself. To find out what I was capable of, instead of blindly following instructions. “Teaching us. Making sure we can find our way home.”

“Those are secondary,” Addie said. “He wants to find Grandma, and if he can’t do it himself, he’ll use us. He’ll use anyone. He’s training us to keep going once he can’t.”

“You think he knows they’re talking about sending him to a home?”

“I think he’s not as lost as he seems.” She shook her head, rinsed out her cup. “I’m going to write that report.”

After she left, I texted Eliot: U back? Movie night?

The reply was immediate: B there asap.

The textbooks Addie and I had fought over this morning lay scattered across the table. I stacked them neatly, but my mom’s office, a narrow windowless room off the main hall, was locked as usual. The only books I could reshelve were the journals, leather-bound diaries kept by my grandparents and other long-dead relatives, stretching back generations. These days most Walkers kept their journals on a computer, but there was something reassuring about seeing row after row, each stamped with the author’s initials.

The Monty I glimpsed in the journals was nimble and canny, even if he didn’t follow protocol. He relied more on instinct and the deft manipulation of strings rather than the bloodless, data-driven style we were taught in school. His later entries degenerated into ramblings about the Consort and his attempts to find Rose. I didn’t read those volumes as much.

My grandmother’s journals were more like scrapbooks: a few maps, lots of notes about medical cases she’d treated, home remedies and recipes for the desserts Monty loved, brief melodies she’d composed.

When I was a kid, I’d read my grandparents’ journals again and again, looking for clues about where Rose had gone and how Monty had searched for her. I’d thought if I could find her, he’d be restored—not just my beloved, dotty grandfather, but the brilliant Walker contained in those books. He’d be happy, and I’d finally meet my grandmother instead of only hearing stories.

I knew better now. Too much time and too many worlds had passed to find my grandmother. The best we could hope for was to keep Monty from losing himself, too.

I headed into the living room, picking up my mom’s viola and running through a few arpeggios, fingers dancing over the strings. The lively, complicated scales usually did the trick when I wanted to fend off melancholy.

Eliot let himself in the back door, calling, “Miss me?”

“Like you wouldn’t believe.” I met him in the kitchen and gave him a quick hug. “Have you been out this whole time?”

“Yeah. Tricky stuff today.” He grabbed a can of pop from the fridge and swallowed noisily. “Boring without you.”

“Naturally. Did anyone ask about me?”

“Callie said you should call her. Everyone’s bummed you’re gone.”

I wanted to believe him, but my phone had been awfully quiet since the sentencing. “What about Shaw? Did he say anything?”

Eliot settled into the blue brocade armchair, lacing his fingers behind his head. “ ‘Be nice to Addie.’ ”

“Pfft. He knows what she’s like.” I played another arpeggio, pleased. Shaw was on my side. If we could prove the cleaving wasn’t my fault, he would back me up with the Consort.

“I went to the Archives after class,” he added. “Pulled a bunch of files and read them on the way home.”

My pulse kicked up. “What did you find?”

“Nothing yet. A lot of the data was lost in the cleaving. I’ll keep looking.”

I tried to sound upbeat. “Did Shaw like the map program?”

“I’m not ready to show him.”

Eliot would be eighty before he was ready—he was a total perfectionist. Usually it made me nuts, but this time he was right.

“Yeah, the software’s glitchy. I meant to tell you yesterday.”

His eyebrows shot up. “What did you do to my map?”

“I was testing it during history, and the display kind of . . . exploded.” I waved my bow around for emphasis.

“Why didn’t you mention it?”

“I rebooted and it looked fine. Besides, it wasn’t like we had a lot of time to chat yesterday.” Between my detention and his training, I’d barely seen him.

“It’s working now,” he said, sweeping his fingers over the screen. “What were you doing when it crashed?”

“Nothing! I was sitting in class, testing the range, and it froze. I took it back to the music room so I could check things out in person, and it started working again.”

He scowled. “I wish you wouldn’t Walk by yourself.”

“Shhhhh.” Before he could scold me—or ask who I’d seen—I added, “There should have been a million pivots coming from the music room, but there was only one. What’s up with that?”

“Only one?” He paced around the room as he worked. “You’re sure?”

“Yes, I’m sure. Saw it, heard it, felt it.” Rather than watch him wear a path in the carpet, I started playing again, trying to recreate the melody I’d heard at Grundy’s. “I bet my mom can figure it out.”

“Quit goofing around,” Addie called, coming downstairs. “And don’t bother Mom. She doesn’t have the time to fix your latest gadget, Eliot. No offense.”

“None taken,” he muttered.

“It’s not a gadget,” I said, tucking away both the viola and the memory of Echo Simon. Addie’s easy dismissal of Eliot rankled. “It’s a map. A real-time map. And it’s amazing.”

“Real-time? Let me see.” She plucked the phone out of his hands.

“There are a few bugs I need to work out,” he said.

“Let’s bring it with tonight,” I said. “Test it again.”

“You’ve been Walking with it?” she asked sharply.

“I’m not allowed to, am I?” Which was not exactly a denial, and Addie knew it. She also knew she couldn’t prove I’d done anything wrong. I let her stew and turned to Eliot. “We should take off.”

“Your wish is my command,” he said, easing the phone out of her grip.

“You two aren’t going out tonight.” She raised her eyebrows, a perfect imitation of my mom. “We’re not done training.”

“Don’t you have friends? Or a date? Something to do that doesn’t involve sucking the joy out of my life?”

“For your information, I did have plans tonight. But since I’m not interested in rehashing the adventures of my delinquent baby sister, I decided to pass.” She didn’t look too upset about it.

“That’s the stupidest excuse I’ve ever heard,” I said. “As if you’d even mention me to your friends. What’s the real reason?”

“I don’t need to justify myself to you. Get your coat, Del. We’re going to a basketball game, and you’re going to map it.”

“Are you joking?”

Her mouth was a tight line. “Do I look like I’m joking?”

“You look like you need to get—” Eliot jabbed me in the ribs, and I glared at him. “What? She does.”

“Not helping,” he muttered. He gave Addie an apologetic half smile. “We kind of have plans. It’s Saturday. Movie night.”

“She knows it’s movie night,” I said. “Saturday is always movie night. She’s just being a bitch.”

Addie sniffed. “Nice, Del. Very classy.”

“You can’t stop us,” I said.

“Can’t I?” She brandished her own phone like a sheriff’s badge. “I talked to Mom, and she agreed with me. Ask her yourself—they’ll be home any minute.”

“I’m going to kill her,” I told Eliot through gritted teeth, following Addie to the kitchen. “Smother her with a pillow. Garrote her with a violin string. Maybe a poisonous snake in her bed. Aren’t you glad you’re an only child?”

“It has its advantages,” he admitted.

I was tempted to start in on my mom as soon as my parents walked in the door, but she looked so exhausted—bags under her eyes, hair falling out of its usual neat bun, skin pale with fatigue—I bit my tongue.

“Eliot,” she said warmly. “I feel like I haven’t seen you in ages. How are you?”

“Good. Dad says you’re keeping him busy.” Eliot’s father led another one of the teams Mom worked with.

“Never enough hours in the day,” she said with a weak laugh, and then turned to me. “Out with it, Del. What’s wrong?”

“Addie says I have to go to a basketball game, but it’s movie night!” When she looked unimpressed, I added, “I’ve spent the whole day training and now she wants to hijack our plans.”

“Quit whining,” Addie said. “You two can try out his map gizmo another time.”

“Map gizmo?” Mom asked, sitting down at the table. Monty wandered in and took his usual seat.

Eliot handed over the phone, bashful and proud mingled together. For few minutes, my mom was lost in it, asking him questions and half-listening to the answers. I tried not to feel hurt that a computer program got more attention than me.

“Impressive. Can I get a copy of the software?” asked my dad. “Could be handy out in the field.

“The code needs a few tweaks,” Eliot hedged.

“No time like the present,” my mom said, shooting my dad a look. “Send us a copy, Eliot. Tonight.”

My mom usually encouraged Eliot’s inventions and gadgets, but never with this kind of gravity. If my parents wanted the map, it wasn’t for entertainment purposes.

“Mom, Addie’s not allowed to take over my whole life, is she?”

“Your sister knows better than to abuse her position.” She gave Eliot a sympathetic smile. “It’s a shame you two won’t have as much time together, with Del’s . . . new situation.”

She was right. With Eliot on his regular training schedule and me at the mercy of a power-crazed Addie, we wouldn’t be hanging out the way we normally did. Eliot was one of those parts of my life that was so familiar I barely noticed it, much like the Key World. He was my constant. The prospect of him moving on to apprenticeship without me pinched my heart.

“The three of you can go together,” Mom said. “Addie’s right—sporting events are a great way to practice mapping. And, Eliot, you can test the software in a high-stress situation. Everybody wins.”

Addie smirked at me. “Told you so.”

Monty pushed back from the table, his chair squeaking on the hardwood. He’d been so silent, I’d forgotten he was there. “Sounds like a plan, girls. I’ll get my coat.”

Addie’s jaw dropped, and it was my turn to smirk.

CHAPTER EIGHTEEN

HALF AN HOUR later the scent of popcorn and nachos filled the air—but instead of the maroon carpet and plush chairs of the movie theater, it was hardwood floors, ancient bleachers, and the staccato squeak of sneakers against the thud of dribbling basketballs. The field house was packed for the first home game, and the four of us were stuck in the nosebleed section.

“Sporting events tend to create really dense concentrations of pivots,” Addie said. “Emotions are running high, which leads to more emphatic decisions and more significant repercussions, and the game itself is a compressed cycle of choices and reactions.”

“Lots of choices,” Monty translated around a mouthful of hot dog. “Lots of branches. Plenty to see, and a familiar face, to boot.”

He nodded toward Simon, bushy eyebrows waggling. I pretended not to know what he meant.

The number of pivots opening and closing around us was dizzying. The sound was like the sweep of wind through tall grass, or a thousand birds taking flight—all flutter and rush and thrill. So many worlds, dangling in front of me like brand-new songs waiting to be played.

Rather than explore, I was stuck with my notebook, marking every pivot that sprang up: people choosing where to sit, the players’ actions, the referees’ calls, and the coaches’ directions. It was a tedious, mind-numbing job, and I fought the urge to shove Addie down the bleachers in retaliation.

While I worked longhand, Eliot analyzed the scene with his phone, the lights scattering and twisting like a kaleidoscope. He barely lifted his head to watch the game. No matter where I looked, my gaze kept wandering back to the court.

Back to Simon. I wouldn’t have argued quite so much if I’d remembered he would be here. The thought made me feel shallow, so I pushed it away and focused on the sight of him pounding down the court, shouting instructions to his teammates. I’d watched him for years, but tonight was my first basketball game. He moved with an urgency that surprised me. The lazy grace that marked his everyday movements was gone, replaced by a sharpness that verged on anger.

It was easy to sense the pivots Simon created. I didn’t need to look at Eliot’s display to see the strength of those branches—I could hear them, the tangle of realities tantalizingly complex.

Next to me, Eliot jerked in surprise.

“What’s wrong?” I had to shout to make myself heard over the crowd.

“Your partner,” he said, tapping the screen. “Watch.”

Bright dots were scattered across the display, smaller pixels clustering around them. “That’s him,” Eliot said, pointing to a pulsing light. “He’s drawing the other branches in.”

I hadn’t heard it, because I’d been so focused on Simon himself. But now, seeing the entire court in miniature, the interplay was obvious. Simon’s pivots fed off the smaller lights around him, increasing with every passing moment.

Monty peered over Eliot’s shoulder, then down at the floor. “You don’t see that every day.”

“What is it?” Eliot asked.

“A Baroque event.” Addie tilted the phone toward her. “One branch in a group of similar frequencies causes the smaller ones to shift. Once enough of them start to shift, they combine, like they’ve been transposed. The resulting branch is much stronger. They’re not super common, but you see them at sporting events sometimes.” She launched into a more detailed explanation, filled with technicalities and citations. It was like listening to someone read their term paper out loud.

“So it’s a transposition?” I asked. Eliot slanted me a look, no doubt remembering how we’d transposed Doc Reese’s science test.

“Not exactly,” she said. “Transposition occurs in newly formed Echoes, before the frequency locks in. Baroque events happen in established Echoes—they’re a lot more complex.”

“What causes them?” Eliot asked.

“Nobody knows,” she replied. “So long as the end result is stable, it’s not a problem. These are the right conditions for it, though.”

Below us the Baroque event was finally audible. It was like listening to an orchestra tuning up—myriad pitches colliding with one another, making minute adjustments. Not even the regular, everyday game noises—the crowd’s stomps and yells, the refs’ whistles, the cheerleaders’ chanting—could mask the sound spreading through the field house.

“It’s kind of cool,” I admitted, watching the pivots forming in Simon’s wake.

The halftime buzzer blared, putting a stop to the Baroque event. We were ahead, 52–37, and the bleachers shook with the crowd’s enthusiasm. The team headed for the locker room, fists pumping, but their absence caused the pivots to fall quiet.

Eliot stood. “Nacho run?”

Addie looked repulsed. “That cheese is nothing but artificial dyes and hydrogenated fats.”

“I’m living on the edge,” he said cheerily. “Come on, Del. You said you wanted popcorn.”

“Popcorn?” Monty said, but Addie caught his sleeve.

“We’ll stay here,” she said. “Be back before halftime’s over.”

Taking me by the hand, Eliot led me down the bleachers and into the crowded lobby. Children darted through the crowd while parents chitchatted, and our classmates clustered together, tight-knit little groupings that didn’t admit newcomers.

“You hate nachos,” I said.

“I didn’t want to talk in front of the others. Tell me exactly what the map looked like before it crashed yesterday.”

“One big light. Took up the whole screen.”

“What did it sound like when you crossed through?”

“Strong,” I said, thinking back. “I couldn’t have stayed longer than an hour, tops.”

“I think you saw the remnants of a Baroque event. Same as now, lots of pivots combining into one. You came in at the end, after the branches were absorbed.” His hands traced paths in the air as he spoke. “I bet another one forms during the second half. Do you think Addie would let us take a look?”

“Not unless we spike her pop.” But the lure of exploring trumped my concern about Addie. “We could go without her. Wait until she’s distracted and check it out.”

“She’s turned you in once already,” he warned. “Don’t give her the chance to do it again. Let’s ask.”

Halftime was ending. Through the doors we could hear the pep band playing a fight song, heavy on the trombone and the bass drum.

“Guarantee you she’ll say no.” I shrugged. Even though doing the sensible thing fit me like a pair of someone else’s shoes, I could see the logic in it. We headed inside and made our way up the stairs. “But you can try.”

Addie spent the second half lecturing us on branch theory and Walker protocol. Monty napped, despite the deafening noise of the crowd. Eliot’s eyebrows shot higher and higher, his posture ramrod straight as he compared the action on the court to his display. I kept my eyes on Simon and the Baroque event.

Even without looking, I knew the minute Eliot’s map crashed—it was the same moment the pivots cramming the floor coalesced into a single, deeply resonant one, tolling like a bell. I clapped my hands over my ears. Even Monty jolted awake.

“And that is how a Baroque event works,” Addie said, like we were kindergarteners and she was the put-upon teacher. The game ended moments later, the crowd on its feet, roaring triumphantly.

Simon led the team through a complicated handshake ritual with the opposing squad, then huddled with his own on the sidelines. He’d played nearly the entire game, turning his uniform dark with sweat and his face ruddy. The triumph in his expression verged on cockiness, as if their victory had never been in question. Fists pumping, the team swarmed into the locker room.

As the crowd dispersed, I turned to Addie. “Did they lose, in the Baroque Echo?”

“Impossible to say without crossing through.” Before I could suggest we do exactly that, she held up a hand. “I’m not taking you into a world we haven’t planned for, Del. It’s not safe.”

I shot Eliot an “I told you so” look.

“We’ll stay on this side,” Eliot promised, towing me down the bleachers.

We hovered on the sidelines until the gym was nearly empty. Pivots covered the court, their edges brushing against me like moths’ wings. Ghosts of previous games, they were unaffected by the Baroque event.

I tucked my hands in my coat pockets and zeroed in on the Baroque pivot. It was centered on a curving red line on the far side of the gym, the edges so pronounced that if I hit them at the wrong angle, it would be like walking into a doorframe. Across the room Addie was explaining the finer points of Baroque events to Eliot, who looked like he was longing for escape.

A basketball rolled into my ankle. I picked it up, surprised by the weight of it. Tentatively I dribbled it, listening to the rhythmic whump as I memorized the new frequency. Maybe I could explore it during school, when Addie wasn’t around to catch me.

Out of nowhere Simon swiped the basketball away mid-bounce.

“Gotta keep your guard up,” he said, evading my attempt to steal the ball back. “I didn’t peg you for a basketball fan.”

“I’m not.” I swallowed, my throat suddenly dry. His hair was damp and disheveled from the shower, his expression curious. “This is my first time. Congratulations, by the way.”

He glanced over at the scoreboard. “It was okay.”

“You won. By twenty points.” I was pretty ignorant about sports, but even I knew that was a good thing.

“True.” He made a show of looking around. “Want to know a secret?”

“Always.”

He leaned in, his fingers skimming my shoulder, his breath warm against my ear. “It’s more fun when it’s close.”

I ordered myself not to blush. “Is that so?”

“Winning’s always better if you have to work for it.” He handed me the ball. “Shoot a free throw.”

“I can’t make a basket.”

“Have you ever tried?”

“In PE. Not pretty.”

“Don’t be so sure. Watch.” He took the ball back and stepped to the line. I watched the shift in him, the way his awareness narrowed to the strip of hardwood, the ball, the net. I’d been on the receiving end of that kind of focus the other night, and the memory stole my breath.

He dribbled twice, raised the ball with his fingers spread wide, and shot, wrist snapping down and hands hovering in the air. I heard the rustle of the net and the bounce of the ball, but my attention was riveted on Simon, who dropped his hands and smiled.

“Very nice,” I said.

“That shot won the state championship last year,” he said. “In overtime.”

“I think I remember hearing about it,” I said dryly. No one had talked about anything else for a week.

“Best day of my life, winning that game. They even let me cut down the net.” He scooped up the ball and pressed it into my hands, his fingers covering mine, his frequency strong and true. “Now you.”

“This is your thing, not mine.”

The smile spread, his eyes crinkling in amusement. “Scared?”

I lifted my chin. “Hardly.”

“Then let’s go. Feet on the line, Sullivan.” He spun me toward the free throw lane, poked a finger into the small of my back, and prodded until I was standing where he had been. “Show me what you’ve got.”

The ball barely made it to the backboard. “See? Hopeless.”

“Take off your coat,” he ordered. “Your range of movement is restricted.”

I struggled to pull my arms out of the sleeves, and he helped me, pulling it off with practiced ease and a wolfish grin.

“Okay, you’re right-handed, so put your right foot here”—he nudged my boot with the tip of his shoe—“and point your toes toward the basket.”

My limbs felt stiff, like a puppet’s, like I’d forgotten how to move.

“Bend your knees a little,” he said, setting his palms against my shoulders. “Arms up. You’re shooting with your right hand—the left is only there for balance.” With every command, he touched me, the gentle pressure of his fingers making me light-headed. “Give it a try.”

The ball sailed into the backboard and careened away. “Told you.”

“Nobody likes a quitter.” He retrieved the ball, spinning it like a top. “So, you came to cheer me on in our home opener? I’m touched, partner.”

“My sister wanted to come.” I tilted my head toward Addie and Eliot, who were half watching the map, half watching me, and wholly unhappy. There was no sign of Monty—but I’d let Addie deal with him this time. “I’m grounded, unless I’m with her.”

“And here I thought you cared.” He tossed me the ball and stood directly behind me, his arms coming around to position my hands. “Fingers spread out. You need backspin. And keep your eyes on the back of the rim.”

I fought the urge to turn and face him. He was the wrong Simon for those kinds of thoughts. Instead I concentrated on the solid expanse of his chest against my back, the way our hands looked together—strong hands, both of us, for entirely different reasons.

His voice was rich and teasing. “Did you do something really bad to get grounded? Please say yes.”

I stared straight ahead. “Long story. Suffice it to say I have a problem with authority.”

“Shocking.” He laughed. “Shoot, Del.”

His hands guided mine, and the ball arced through the air, sliding through the net with a faint whisper.

“I did it!” I whirled to see the smile break across his face, mirroring my own.

“With my help,” he pointed out. He tugged the little braid I’d woven into my hair. “Grounded for scandalous reasons? Cutting class? I’m getting a very clear impression of you.”

“Oh?”

“You’re trouble.” He made it sound like a good thing.

“Funny. That’s what people tell me about you.”

“You should listen,” he said softly. His skin radiated heat, as it had the other night, and the memory made me bold enough to step closer.

“Simon!” Bree ran up, throwing her arms around his neck. “You were amazing! It’s like they didn’t even show up, you guys were so good! And that three-pointer was incredible—I swear, the scout from Arizona didn’t even look at anyone else.”

Simon eased away, his smile fading. Bree tipped her head to the side and gave him a beseeching look. “Can I get a ride with you to Duncan’s party? Cassidy has a ton of people in her car already.”

“Yeah, sure.” He turned to me, a note of apology creeping into his voice. “Party. At Duncan’s.”

“I heard.” Cold settled over me, and I scooped my coat off the floor, avoiding his eyes.

“You could probably come, if you wanted. It’s pretty low-key.”

“Duncan won’t want a bunch of people he doesn’t know showing up,” Bree cut in. “We can’t go around inviting everyone.”

For one crazy moment I thought he might do it anyway. He had enough social currency stockpiled that he could have brought a leper—an actual leper, not just a social one—and people would have been okay with it. He hesitated, and his choice was obvious.

I beat him to the punch. “Grounded, remember? And high school parties aren’t my scene.”

“Really,” Bree said, dripping sarcasm. “Why’s that?”

I smiled at Simon, radiating nonchalance as hard as I could. “No challenge. You two have fun.”

“Del,” Simon began, but I was already heading for the door. Always better to be the one leaving.

CHAPTER NINETEEN

Aside from the need to keep Walkers secret from Originals and Echoes, romantic relationships are frowned upon for another, more pressing reason: The future of our people and the Key World depend on maintaining the genetic line.

—Chapter Four, “Physiology,”

Principles and Practices of Cleaving, Year Five

YOU LIKE HIM,” Eliot said as we sat on the front porch after the game.

“Simon? Hardly.”

“You’ve been acting weird ever since Powell paired you up. Walking when you’re not supposed to. Flirting with him in class. He was hitting on you tonight, and you let him. Evidence doesn’t lie.”

It was Eliot’s guiding principle, but that didn’t stop me from denying it.

“Did you miss the part where Bree told him not to invite me? And he listened?” I dug my toe into the floorboards and pushed off. The wooden swing creaked loudly as we swayed.

“You should stay away from him,” Eliot said. “He makes you unhappy.”

“This conversation is making me unhappy.” Eliot never liked the Walkers I went out with either, and I wasn’t in the mood for this talk. Besides, I wasn’t going out with Simon.

“There’s something weird about the guy. Two Baroque events in as many days, and he’s at the center of both? Let me look into it before you start throwing yourself at him.”

I scowled. “I’m not throwing myself at him! He’s not even my type.”

“Who isn’t your type?” asked Addie through the screen door. “That basketball player? The grabby one?”

“Forget it.” I slouched down.

“You know it can’t go anywhere,” she warned. “He’s not a Walker.”

“He’s not anything,” I said. “Just a guy.”

“Good,” Eliot and Addie said in unison.

The order against Walker-Original relationships was stupid. Even the Consort turned a blind eye to it until after apprenticeship, when people started settling down and relationships turned serious. I understood the need to pass along our genes; without future generations of Walkers, the Key World would eventually crumble. But I wasn’t looking to marry Simon. I wanted . . . I didn’t know what I wanted, but a white picket fence wasn’t it.

Addie went back inside. I must have looked like an idiot, flirting with Simon only to have him leave with another girl. Embarrassment curdled in my stomach.

Eliot slung an arm over my shoulder. “Find someone else, Del. Someone who’s actually worthwhile.”

I stiffened. “Don’t tell me what to do.”

“I’m not. I’m saying be smart, for once.”

“You’re the relationship expert now? I don’t see you getting anywhere with Bree Carlson—or anyone else.” The words came out nastier than I intended.

“Why would I want to?” His brow furrowed. “Simon’s the one who bailed. How come you’re mad at me?”

“Why would I be mad? I love hearing Simon Lane couldn’t possibly be interested in me. Keep going. Tell me more.”

“That’s not what I—” he started to say.

“You’re jealous,” I said. His face went cold and remote, and I knew I should shut up, but my humiliation had been festering since the game, turning to anger, thick and oily in my veins. I couldn’t stop myself. It was leaking out, contaminating everything, poisoning the one good thing I had left. “You’re jealous because I actually go after what I want, and I get it.”

“You didn’t tonight,” he said, voice like acid.

“At least I tried. You’d rather spend your time analyzing data than take an actual risk. Jesus, Eliot. Find a girl. Make a freaking move. Maybe then you’d get the hell off my case.”

“And maybe if you’d pay attention to anything except yourself for five minutes—” He broke off, like he was stuffing down the words he wanted to say. “You want to be mad? Get mad at Simon or Bree. I saw your face when he chose that party over you, and evidence doesn’t lie. Don’t tell me that you’re not falling for him.”

“And that’s your business?”

“You’re . . .” He dropped his head, took a deep breath, and met my eyes. “You’re a pain in the ass, and tonight you’re kind of being a bitch, but you’re my best friend. I don’t want you to get hurt.”

The anger leached away at the truth in his words. “You think he’ll hurt me.”

“He already has.” He threw up his hands. “Do what you want, Del. You always do.”

He jogged down the porch steps without another word, shoulders hunched, hands jammed in his coat pockets. I wasn’t the only one who was mad.

In sixteen years we’d fought only a handful of times. Each one left an awful, hollowed-out feeling in my chest. Now the hollowness was tinged with guilt. Eliot had always been unfailingly, unquestioningly on my side. What if I’d broken our friendship? What if it couldn’t be mended?

Inside, Addie was drinking a cup of tea and reviewing a map. “You two were going at it pretty good.”

“I’ll fix it.” Some things, you had no choice. And fixing Eliot and me was one of them.

“Good luck with that.”

“It’s late,” I said, surprised by how quiet the house was. “Where is everyone?”

“Monty’s asleep. Mom and Dad are holed up in her office. Again. I wish they’d tell me what the problem was.”

“Good luck with that,” I mimicked, and she glowered at me, her frustration clear.

My entire life I’d watched Addie follow the rules, gathering praise and attention. There’d been no way for me to match her perfection, much less exceed it. Eventually I’d stopped trying. Addie and the rules were interchangeable, and I’d grown to resent them both. I’d never given any thought to why she was so driven. If people love you because you’re perfect, what happens when you screw up? Constant perfection was its own kind of pressure, I realized, and felt an unexpected rush of sympathy.

“He’s right about that guy,” Addie said. “What’s his name?”

“Simon,” I said after a moment’s hesitation.

“You were talking to him at the park, weren’t you? Before the cleaving.”

“His Echo,” I corrected. Hair so long it obscured his eyes, leather cuff, warm hands and a warmer invitation.

“You shouldn’t get involved with him, especially if Eliot thinks he’s bad news.”

“Eliot’s wrong.”

“Eliot is biased, but he’s not wrong. Be careful.”

I rolled my eyes. Sisterly bonding time was over.

Upstairs, I flopped onto the bed, the ancient springs squeaking in protest. Above me, my origami garlands swayed in a draft from the window. Hundreds of stars, twins to the ones I’d scattered while Walking.

Including the one I’d left with Simon, back in Doughnut World.

The Simon who wanted me. The one who’d left a show and a room full of people to spend time with me. The one who didn’t judge or scold or do anything except make my heart quicken and my blood sing.

Echoes weren’t real, but I was falling for one. Or was I falling for the real Simon, and using his Echo because it was the only way to be with him?

I eased out of the bed, holding my breath. My backpack was still stocked from today’s training session—duct tape, Swiss Army knife, matches, candy, and now, Monty’s lock picks—and its weight was comforting. I might be reckless, but I wasn’t stupid.

I’d snuck out plenty of times before, but never with this much at stake. The smart thing to do was to stay here, figure out a way to make Eliot forgive me, and convince my parents I had learned my lesson.

But ask anybody: Addie was the smart one.

CHAPTER TWENTY

EVEN THOUGH PIVOTS created by Walkers didn’t last, most houses contained at least a few—previous owners, plumbers, the occasional visitor. We might not choose to spend time with Originals, but some interaction was unavoidable. The pivots riddling our house were old, but they worked—and provided the perfect escape route.

I tiptoed across the room, feeling for a rent in the air next to my music stand. The edges were soft as mist when I eased my way through, listening for Doughnut World’s frequency.

I’d been using this passage out of my room for years, ever since Monty had shown me how. Even though our house existed in countless Echoes, we weren’t the owners. Sometimes I’d cross through and find it abandoned and in disrepair, but most of the time, someone else had moved in. I’d grown accustomed to seeing rehabbed master suites, dusty storage catchalls, and home offices, though I never got over the sensation of being a burglar in my own house.

This time I crossed into an empty attic, exactly as it looked before I had moved up here in elementary school. I headed downstairs, surprised to see familiar furniture and pictures on the wall. The house was dead silent and covered in a thick layer of dust, but definitely ours.

Weird as it was, I was more interested in finding Doughnut Simon.

By now he’d probably forgotten me. But I could remind him. I could try again. It had to be better than my real life, even if only for a few hours. I let myself outside and crossed the shadowy overgrown lawn.

At the living room window a curtain fluttered, ghostly white, and fell still.

I flattened myself against the trunk of a maple tree, trying to discern any hint of movement. Had my parents come up to check on me and tracked me through the pivot? Was the Consort monitoring me without my knowledge?

Nothing. The curtain hung straight and unmoving as clouds scudded across the sky. The only sounds were the wind in the leaves and Doughnut World’s frequency, even stronger than last time.

I exhaled slowly and set out to find Simon.

I tried Grundy’s first. There was a half-decent jazz combo playing, but no Simon. I knew where his Original lived, but couldn’t quite picture this version hanging out at home on a Saturday night. Why had I thought I’d know him well enough to guess his movements?

In a corner booth I spotted the basketball coaches, boisterous and laughing over a pitcher of beer. Game night. If the coaches were here, the kids were celebrating elsewhere.

Duncan’s party. I might have landed in another universe, but a postgame party was a given. And even if Echo Simon wasn’t on the basketball team, he moved with the innate confidence of someone who knew he’d be welcomed in.

The wind cut through my coat as I headed toward Duncan’s neighborhood. If there was no party, or if Simon wasn’t there, I’d end up with hypothermia for nothing. If he was . . . it would be worth it.

My hunch paid off. I spotted the familiar black Jeep at the same time I heard the bass thumping against the windows of a redbrick colonial. I started for the front steps, then stopped. Simon might not be alone. He could have come to the party with Bree, or another girl. He might want to stay with them. It had been so easy to fall into thinking of him as “my” Simon, but that didn’t make it true.

I blew on my fingertips, checked my watch. Past midnight. I could wait for a little while. There was time to scope out the situation, if I didn’t freeze first.

That’s when the rain began. It was thin and nasty and sharp, finding its way down the back of my neck. I eyed the Jeep, looking cozier by the minute, and sent up a silent thanks that Monty’s lessons in petty crime weren’t limited to pickpocketing.

Pulling out my picks, I set to work, hands aching with cold. A minute later I was inside—half-frozen but out of the wet—and replaying my fight with Eliot.

Two Baroque events in as many days, and he’s at the center of both, he’d said. But Original Simon’s frequency was fine. I’d heard it, loud and clear, when we’d touched at the game. If Baroque events were common during sports, it made sense that the captain of the basketball team would be involved. And there were a million factors that could have triggered the problem with Eliot’s map. He was blaming Simon because he was worried about me.

Tomorrow, after Eliot got back from training, I’d go over to his house. We’d fix his map and then we’d be fixed too.

The sound of the door opening made me bolt upright and shriek—which made Simon jump back and swear, then peer at me in the glow of the dome light.

He could still see me, as if our previous contact had carried over. I held my breath, hoping his memories had too.

“You do know how to make an impression, don’t you?” he said, and climbed inside.

“Rain again,” he added as it pattered against the windows. “Am I only going to see you when it’s raining?”

I frowned. “What do you mean?”

“I looked for you at school.”

“You did?” The idea was flattering. I wouldn’t have been there, of course. He would have seen an impression of me, like a figure in a dream that you couldn’t quite catch. I allowed myself to imagine a version of Washington where Simon sought me out. “My attendance is . . . spotty.”

“Is that why you’re grounded?”

“Not exactly.”

“Is it because you break into people’s cars in the middle of the night?” He lifted my hands to his mouth and blew gently, warming them. I scooted closer.

So much easier to be bold with this Simon, and nothing was more bold than honesty. “I wanted to see you.”

“You could have come inside,” he said.

“I wanted to see you. Not the rest of the school.”

His gaze settled on me, and I stared back, my heartbeat prestissimo, faster than fast. “Did you break out to see me? Or to piss off your parents? I’m not complaining either way.”

I thought back to the jumble of emotions I’d been swamped by tonight, propelling me out of one reality into another. “It was a crappy night overall.”

“Poor Del,” he said, and brushed the back of his hand over my cheek, the touch whisper soft, and then his fingers slid under my hair, warm and deft. “Bet I can cheer you up.”

I tilted my head to the side, pretended to consider the idea. “Okay.”

“I’m better than okay.” He was close enough now that, even in the darkness, I could see the corner of his mouth curve, irresistibly.

“Prove it.” I grabbed the edges of his coat, the leather soft under my fingertips, bracing myself.

His mouth came down on mine—no hesitation, no uncertainty—and while I felt the potential crackle around us, a thousand worlds coming to life at the touch of his lips, every one underscored that this moment was exactly what he’d wanted.

What I’d wanted too. The recklessness I felt around Simon was different—sharper and hungrier than my usual impulsiveness. I couldn’t stay forever, but he trailed kisses along my throat, his hand sliding up my spine, and I knew I couldn’t stay away, either.

The idea should have worried me, but instead it thrilled me more, made me drink him in as deeply as I could.

He drew back, rested his forehead against mine. “That enough proof?”

The words were a challenge, but the gesture was sweet. Rather than answer, I angled my head and kissed him again, slow and thorough, learning the way his hair threaded through my fingers, and the way his breathing changed at my touch, and the tempo of the pulse in his throat. I learned Simon, and if a small voice warned me that this wasn’t really him, I ignored it. Ignoring things I didn’t want to hear had long been one of my specialties.

“Tell me about the crappy day,” he said, when we finally came up for air.

His words brought it back—and I shook my head, trying to dislodge those thoughts. There was no room in the Jeep for anything except the two of us. “It’s nothing.”

“Not if it made you look so sad.”

I traced the bow of his mouth with my thumb, and he caught it between his teeth. Startled, I laughed. “I’m not sad now.”

“Glad to hear it. We should go somewhere.”

“What’s wrong with here?”

He peered out the front window. The party was winding down, people passing by on the way to their cars. “It’s a little public for what I was thinking. And cold.”

I shivered for reasons that had nothing to do with the temperature. “I should get going.”

He let go of me to rummage in the cup holder, coins jingling. “That’s what you said last time.”

He held out his hand. My star rested in the curve of his palm, the points rounded as if they’d been worn away. The Key World frequency coming off it was barely audible. I brushed a finger along one edge, and the signal strengthened, like a flower unfurling in the sun.

“You kept it.”

“You disappeared,” he said. “It was proof you were real.”

Was the star—or rather, the frequency it carried—why he remembered me? Hard to believe that such a small dose of the Key World could have an effect on him, but his reaction said otherwise. “I’m real. I promise.”

“Let’s go back to my house,” he murmured, lacing his fingers with mine. “Iggy would love to see you. We could watch a movie, or hang out. Get to know each other.”

“And then . . .”

There was a wicked tilt to his grin. “Then we’ll see what happens.” He kissed me again, pressing me back against the door, his roaming hands giving me a very clear picture of what would happen. “Say yes.”

“Another time.” Disappointment flashed in his eyes, so I added, “I have to get back before someone figures out I’m gone.”

“What about school? Will you be around?”

“I’ll find you,” I said, and tugged my shirt back into place.

“Let me drive you home.”

I didn’t want to explain my abandoned Echo house. “Better not. I need to sneak back in.”

“It’s raining.” When I hesitated, he simply put the car in drive. “Where to?”

In minutes we were parked at the end of my block, the rhythmic whoosh and slide of the wipers filling the car. “Thanks for the ride. And the cheering up.”

“Anytime.” I reached for the door handle, and he pulled me back in for one last searing, searching kiss. “Don’t make me come and find you, Del.”

He couldn’t, even if he tried.

I waited until he was gone, then hurried across the yard and up the steps, checking for any signs of movement inside. There was nothing; the entire house stood like a tomb, and the door screeched with protest as I opened it again.

My earlier shoe prints were visible in the dust carpeting the hallway, leading back up the stairs to my room. But I saw something else, too: a path through the dust that had been rubbed out. Not footprints, but the marks of someone trying to hide them.

END OF FIRST MOVEMENT