The Unseen World

2009, San Francisco, Boston

“Are you busy? I hope I’m not disturbing you at work,” said Gregory Liston, on the phone.

His voice was warm and familiar; it brought to her, sharply, a memory of Liston’s house. He sounded older, somehow tired, but his voice still had a catch in it that he had never quite lost.

“It’s okay,” said Ada. “No, I’m not busy.” She pressed her fingers to her forehead. Squeezed.

“Are you all right?” she asked, finally, when he didn’t continue.

“Listen, I have a question for you,” said Gregory. It had been five years since the last time they’d spoken.

He was in San Francisco, he said. He was there on a work trip. Gregory had studied mechanical engineering in grad school; now he, too, worked in tech, for a robotics firm based in Houston. But he lived in Boston still, with his wife Kathryn, working remotely from an office space downtown, commuting twice a month to be on site. He was rich now; his sister Joanie, who kept Ada apprised of the family’s comings and goings, had said so. Ada tried to picture him as he spoke.

There was something strange in his voice: something he wanted to share with her. She could read him, still, despite how fully they had fallen out of touch; she recognized from their youth the quality in his voice that indicated he was nervous and excited.

“This will sound strange,” said Gregory. “But were you ever able to decrypt the letters on the disk David left you? All those letters in a row,” he said.

She paused, took a breath. Always, the sound of her father’s name produced a response in her that was nearly physical: she heard it, she spoke it, so rarely now. There were so few people in the world who would understand him, what he had meant to her, what he had left her with.

“No,” she said, “I never have.”

In fact, she had stopped trying to break it several years before. She still had in her possession, someplace in the supply closet in her apartment in San Francisco, two of the copies of it that she had created along the way; but the original had been lost, years ago, when Ada was in college. One winter break, she had reached up to the top shelf in her closet at Liston’s house to take down the dictionary in which she kept the several documents she had that related to David, including the For Ada floppy disk he had given her. But her hands had come away empty. Liston, when asked, speculated that she must have donated it during one of her rare organizational frenzies, mistaking it for something commonplace, not bothering to flip through the pages to verify its emptiness.

“God, I’m so sorry, baby,” Liston had said — though of course it wasn’t her fault — and Ada had told her not to worry, feigning nonchalance, smiling brightly to show her that it was only an object. The truth was, though, that it had acquired a significance in Ada’s mind that was larger than she admitted. As the last thing that David ever gave her — even if she never solved the puzzle on it — the disk itself had become a totem, a talisman, proof of her father’s good intentions.

Ada had continued, after that, to work on the copies of the disk that she had made, and from the text of the code itself, which she had long ago memorized. But the code, as far as she could tell, was unbreakable. After years and years of concentrated work, she had still not been able to decrypt it — nor had anyone. She had repeated the string of letters to anyone she thought might have an idea. The former members of the Steiner Lab — Liston, Charles-Robert, Hayato, and Frank — had all worked steadily at it throughout the last twenty years, to no avail. She had even posted it in online forums, anonymously, once offering a reward for anyone who could offer a persuasive decryption. At last, one day, Ada had decided sadly that Hayato’s initial question, when she first showed the Steiner Lab the string of letters David had left for her to decode, had been the correct one to ask: Was it possible that David’s thoughts were already addled when he created the disk? And in that moment, she decided that she would try to put the disk out of her mind.

On the other end of the telephone, Gregory was quiet. Her heart quickened.

Before she could reply, Meredith Kranz appeared, hovering, uncertain, in the open doorway to her office. She made small movements with her hands; she was mouthing something to Ada.

“Hang on,” Ada said into the phone, and she tilted it downward, away from her mouth.

“I’m sorry to interrupt,” said Meredith. “I was just wondering if I could borrow you for two seconds before the meeting? I have some questions.” She crossed one leg in front of the other. She looked hesitant and small.

Ada paused. She understood, abruptly, that it had not been Meredith’s idea to do the pitch; that this was another of Bijlhoff’s foolhardy, impulsive decisions. She breathed in and out, once, deeply.

“Sure,” she said to Meredith. “Five minutes.” Holding her right hand up, fingers spread.

“Thank you,” whispered Meredith, her face awash in relief, and she continued to say thank you as she backed out of the door.

Ada returned to the call.

“I’ve never solved it,” she said again.

“It’s been about five years since I tried,” she added.

Gregory was silent.

“Why?” she asked.

“Because I was thinking I might have an idea,” he said.

They would meet, they decided, that morning. There was nothing keeping Ada at the office; she would give Meredith a brief and inadequate tutorial, answer her questions as simply as she could, and send her off. Then she would leave for the day. Maybe, thought Ada, she would leave for good.

The last time she had seen Gregory Liston was in 2004. It was also the last time she had been to Boston.

It was for Diana Liston’s funeral. Ada had known it was coming — for much of the nineties, Liston had fought against recurrence after recurrence of breast cancer, which culminated in a terminal diagnosis in 2003—but it did not lessen the blow of the words as they had been spoken to her by Joanie Liston over the phone.

“She’s gone,” Joanie had said.

“I’m so sorry,” Ada had replied, and it was only after hanging up that she had allowed herself to collapse into violent, convulsive sobs, the kind of weeping in which she had only ever let herself indulge, truthfully, in the presence of Liston herself. She retched. She cried so much in those first days, and so often, that she had to remind herself to drink water, to stay hydrated. She wished for a friend, a companion, someone she could share her grief with. She wished for Liston, whom she had called frequently throughout her adult life to seek advice or comfort. She had been casually dating someone in those days, meeting up once or twice a week with a kind but noncommittal programmer named Gabe; but Gabe did not seem to her to be the person with whom to share this kind of sorrow. Her other friends in San Francisco both did and did not understand; they couldn’t place Liston in Ada’s life in terms that they could relate to. She fit no category neatly. Liston was not Ada’s mother; she was not even Ada’s relative. “A close family friend,” was how Ada referred to Liston, still, though it never felt right. Or, sometimes, “I lived with her in high school.” Only Liston’s children might truly understand, but they themselves were busy, and it felt wrong to Ada to seek comfort from them. Joanie had taken the lead on the funeral arrangements, and she was keeping Ada informed, but separate. “Don’t be silly,” she said to Ada, trying to be kind, when Ada asked what she could do to help. But I want to, Ada had thought. I want to help.

That whole week, she had tiptoed around the edges of the Liston clan, seeking a place for herself, finding it difficult. She was thirty-three that year, and had left Boston at eighteen. She had come home only for some summers and holidays until she was twenty-two, and then rarely after that.

At the wake, she had stood to the side in Liston’s living room on Shawmut Way, fighting back tears. The house was packed, absurd, hot. There was Matty, holding court in the middle of a group of childhood friends, now tall men, some of whom Ada vaguely remembered; there was William, who had expanded over the years into a benevolent, sleepy thirty-five-year-old, already twice married and twice divorced. His daughter Abigail, six or seven, stood next to him, as golden and gorgeous as he had been as a child. There was Joanie with her own brood. There was Gregory, then an engineer in Boston, who had, despite all odds, become a reasonable, functional adult — he could even have been called well-adjusted. He had lost the shyness he had had as a child, when his expression typically vacillated between embarrassment and devastation; it had been replaced instead by a quiet seriousness that made room frequently for flashes of wit. He had surprised Ada on several occasions in her adulthood by producing, as if from nowhere, the exact brand of humor that reduced her to helpless, silly laughter: the absurd humor that David, in fact, had favored. In these moments she looked at Gregory in surprise: Where was this when you were a child? It would have helped him, she thought.

In the crowded living room that day, he stood next to his wife, Kathryn. Ada had been invited to their wedding four years prior, and had gone, bringing her grad-school boyfriend, Jim. Kathryn was tall, taller than Gregory, and WASPy in some unquantifiable way: forthright and assured of her own correctness, maybe. She was beautiful — Ada had done a double-take the first time they had met — and manifested both intelligence and kindness, but she had spent her wedding weekend ordering Gregory around in a way that was so obvious as to be uncomfortable. Ada had one picture of herself and Jim from that weekend — it was shortly before the total collapse of their relationship — and in it, Kathryn’s long arm could be seen outstretched in the background, presumably pointing Gregory toward something that needed to be done. Now, at Liston’s wake, Kathryn was silent while, next to her, Gregory spoke with guests and received their condolences. From time to time she checked her phone subtly.

The rest of the house was filled with Liston’s girlfriends from high school, who knew how to help Joanie without being asked, and with Liston’s relatives, cousins and aunts and uncles whom Ada had met several times a year in high school. All of them looked at her with vague recognition and then surprise. Ada! they said. So good to see you. But it was Gregory and Matty and William whom they embraced firmly, whom they collared and held tight. It was Joanie to whom they said, She was incredible.

The Steiner Lab had come, of course, and Ada stood and talked for a time to Hayato, who himself was holding back tears. After David, out of all the members of the lab, he and Liston had been closest. But all of them left early, much earlier than Liston’s extended family, raucous Irish Bostonians who would stay, Ada knew, until the early hours of the morning, singing Liston’s favorite song (“The Parting Glass,” the Clancy Brothers’ version), encouraging everyone to join in. Ada, too, stayed; she felt she should be there. It felt like asserting something about her life and the importance of Liston in it. But she found that, in Liston’s absence, there was no one there to bring her into the center of things — no one to proudly introduce her to the room.

Toward the end, Gregory, with Kathryn on the opposite side of the room, had approached Ada. He was drunk, maybe; his face was slightly pink; his gaze was sentimental.

“Mom loved you so much,” he said to her. “Sometimes I thought she loved you better than she loved us.”

Ada laughed. She shook her head.

“You were better-behaved than we were,” said Gregory. “That’s for sure.”

“She just didn’t catch me,” said Ada. But of course he was right.

“And David,” said Gregory. He hung his head. “I think she was in love with David for half her life.”

Ada tensed.

“No,” said Ada. “No, they were friends.”

“You didn’t see what we saw,” said Gregory. “Before he got sick. She mooned over him. She confessed it to Joanie when Joanie got older. If he’d liked women I think they could have had a great love story. They made sense together.”

“Oh, I don’t know about that,” she said, vaguely. “I don’t think she was.”

She searched the room for an escape. David had been gone for twenty years now, and still his name now produced in her something akin to pain. She loved her father, still loved him, but it elicited a deep, dull ache in her to think of him, to speak of him — there were too many unresolved questions about him. Over the years, Ada’s vision of David had become something delicate and tense, a raveled knot of emotion that twisted tighter at any mention of him.

“I do,” said Gregory. “My brothers and sister and I talked about it all the time. We teased her about it.”

She smiled ruefully. “Well,” she said. She could think of nothing more to say.

But Gregory was not finished.

“You were both like that,” he said. “You Sibeliuses.” His voice had taken on an edge, and Ada could not identify its source. She searched his face. He looked away. Like what? she wanted to ask, but she felt it was a door that should not be opened.

“I’d better get going,” she said. She lifted her purse onto her shoulder.

Awkwardly, she had hugged Gregory, Matty, Kathryn, the rest of them — even William.

She had said goodbye to Shawmut Way, to the houses on it. First Liston’s house — into which Gregory and his new wife Kathryn would move that same year — and then David’s, which had recently been acquired by its third set of owners since she and Liston had sold it, at last, in 1987. Liston had kept her apprised of its state from across the country whenever they spoke. “The Burkes have it planted nicely,” she told Ada; or, “This new family needs to get someone to mow the lawn.” Ada would miss those reports.

Finally, she had gone back to her hotel. She hadn’t slept. She had lain awake until the sun rose, and then boarded the plane that took her back to San Francisco.

That was five years ago. Since then, she had exchanged sporadic, halfhearted e-mails with Matty, now Matt (a serial dater, a perennial youngest child, who hopped between jobs and girlfriends with equal enthusiasm); had exchanged Facebook likes and messages with Joanie, who texted her photographs of her children (Kenny, the oldest, would be a father himself soon) and complaints about what terrible things Kathryn was doing to Liston’s house. You’d hate it, Joanie had written confidentially. It looks like a beach house or something. White wicker everywhere. Though she had settled into an amicable relationship with William, she still kept her distance from him; they had nothing in common, Ada realized, and they never had. Every so often she sent a line to Gregory, to whom she had been closest as a child; but his replies to her were typically brief, and so after a while she ceased to.

There was nothing keeping her at the office now: Meredith, after all, was leading the meeting. She put on her jacket, stood up, and walked across the main floor — strange looks from her colleagues, from Tom Tsien — and then out the door and into her car. She had suggested, to Gregory, a restaurant called Larkspur, avoiding Palo Alto’s most popular spots. It was a sort of tearoom, someplace that served breakfast and lunch, someplace she hadn’t tried before; someplace, she thought, where she wouldn’t be seen by anyone she knew. She didn’t want to have to introduce Gregory to anyone, or explain what they were doing.

As she drove, she contemplated David.

He existed in a deep recess of her mind as a strange and painful chapter of her own history that she only thought about when she was prepared for sadness. She tried to convince herself that she had come to terms with him; that she was comfortable, at last, with never knowing the truth about him. But she was not certain she had been successful in this endeavor. He was troubled: this was how she had categorized him. The word she used to describe him, always, to friends.

She still had dreams about him, though — regularly, once a week or more — and in them he appeared to her as the face of all the benevolence in the universe. A kind and somehow holy presence that blessed and pacified her, that eased her worry, that calmed her. She woke up from these dreams consoled; but any warm feelings she had were quickly replaced with suspicion, with the unsettling sensation of being lied to again and again — even by her own recollections.

The restaurant was on a side street, in a Craftsman-style house.

When she walked in, she realized that she had gotten there first. She had not wanted to. She was more nervous than she could have anticipated: to see Gregory, yes; but also to hear what he had to say. It had been so long since she had spoken directly to anyone about David.

The place was decorated inside to represent the period of the house’s construction. Light wood and rich colors. She ordered tea. She asked for bread. It came with delicate small pots of jam and marmalade. She waited five minutes, and then ten.

Moments later she received a text from him: looking for parking. be there soon.

And then there he was, Gregory, finally, rushing toward her in an overcoat, a look of apology on his face. He was benevolently inept: he elbowed another patron in his rush to the table, and then stooped down to excuse himself for longer than was necessary, bowing in apology.

There was a moment when Ada half rose from the table, uncertain whether he would expect a hug, but he sat down abruptly across from her and, relieved, she sank back into her chair.

“Cold out!” said Gregory, before he said anything else. He took a piece of bread from the basket, ripped off a piece, chewed quickly. “I thought San Francisco was supposed to be warmer this time of year.”

Ada nodded. It was January. Typically, it was. She watched his jaw as he chewed. It was a day or two past being shaved: his face was thin now, thinner than it had been the last time she had seen him. He had lost the elfin look he had had as a child; but his eyes were still large and inquisitive, his mouth fine and interesting. Now, newly, there were flecks of gray in his hair.

“How have you been? Good to see you,” said Gregory. He seemed nervous.

“I’m good,” said Ada. And she racked her brain for questions she could ask him, so she would not have to answer any about herself. “How’s the house?”

“Oh,” Gregory said vaguely. “Old. You know.”

“And the job?”

“Great,” said Gregory. “Good as it can be, I mean. Too much sometimes, but you know how it is.”

“I do,” said Ada.

“How about yours?” Gregory asked. “How’s Tri-Tech?”

She paused. She wondered if Gregory knew the details of Tri-Tech’s recent troubles. Industry websites had been reporting on the topic for a year, and last week rumors of layoffs had been posted on TechCrunch. Gregory didn’t seem like the type to keep up with industry gossip, though.

Before she could say anything, the waitress came by to ask him for his drink order.

“Coffee,” he said. “Black.”

“And how’s Kathryn?” asked Ada.

Roughly, he ripped off another piece of the bread with his teeth, and chewed it with a sort of aggressiveness, to make it clear perhaps that he could not speak. He looked out the window as he did so.

Ada took a sip of her tea. She wasn’t certain what to say. The silence went on for longer than was comfortable.

“I was hoping to save that for later,” said Gregory. “But what the heck. We’re getting a divorce.”

He shrugged at her, looked at her with wide, defensive eyes.

“I’m sorry,” said Ada.

“Yeah,” said Gregory. “Really knocks the wind out of you.”

She had a vision of him, suddenly, as he had been in middle school: broken, scurrying from place to place, avoiding anyone’s eye. These days he stood up straighter, looked intently at anyone speaking to him. He might even be called handsome, in a way that was subtle enough to present itself slowly, over the course of a long conversation. It was funny, she thought, what adulthood did to a person; William had grown into something nearly unrecognizable, his only attractive quality the unshakable confidence that he had acquired as a child. Gregory, on the other hand, had grown interesting to look at. He had fine dark eyebrows that he raised, one at a time, to emphasize a point. Thanks to years of braces he had excellent teeth, straight and white, and as an adult he smiled frequently. Ada imagined that new acquaintances of his suspected nothing of the trauma he had endured at school when he was a child. But his voice had retained a hint of it: there was a slight, almost imperceptible quaver to his speech, and he still occasionally stammered. Ada heard both qualities, now, as he spoke.

The waitress returned, delivered his coffee; and then, perhaps sensing the gravity of the moment, departed swiftly once again.

“She’s keeping the house, too,” said Gregory.

“No,” said Ada.

“Yup,” said Gregory. “Mom’s house. I’ve got half my stuff in my car already. Mostly old gear and cables and stuff, antiques.”

“Where are you moving?”

“Some new apartment building in Cambridge,” he said. “With a bunch of college kids. Can you believe it?”

“When do you have to leave?” Ada asked.

He shrugged again, ripped off more bread. He was clutching the crust of it in his hand too firmly. It was disintegrating in his grip. “Soon as possible,” he said. “I’m already paying rent at the new place. We’ve been separated for a year already, and she’s at her new boyfriend’s now most of the time, anyway. They’ll probably move into the house together as soon as I’m gone.”

They sat in silence, briefly, until at last the waitress returned to take their order.

“Two scrambled eggs,” said Gregory.

“Nothing, thanks,” said Ada.

Ada sipped her tea. She pictured Liston’s house and David’s house, too, sitting a few lots apart on Shawmut Way. Soon she would know nobody who lived there, and the thought made her feel hollow. For as little as she saw Gregory, she still took comfort in the thought of him living on their old street, bearing inside him the story of his mother, of David, of Ada. It connected her, in some intangible way, to her past.

He stared down at the table. He looked incredibly forlorn.

“Tri-Tech’s failing,” she said, abruptly. “I wouldn’t be surprised if they folded in a year.” It was true, and it seemed right to tell him. A fair trade, a secret for a secret.

“On top of that,” she continued, “I think they might be edging me out. I was supposed to be leading a meeting right now that I was disinvited to this morning.” It was almost funny, as she told it to Gregory: it was a relief to say it. She felt the deep absurdity of it welling up inside her, softening its edges, lessening the blow of having wasted most of her professional life to date on a company that was fundamentally unsound, subject to the ignoble whims of an egomaniacal leader. She was working for an outfit that prized money over ideas. David, she knew, would have predicted a different future for her: and this was the thought that needled her, that pierced her sometimes unexpectedly as she was driving to work each day. This was the guilty whispering voice that kept her up at night.

“I’m thinking of quitting,” she said.

“Oh, yeah?” he asked. “I guess we’re both screwed.” And, for the first time, he smiled.

Gregory reached into the inner pocket of his overcoat then, and from it he produced an object. Silently, he offered it to her.

It was the original floppy disk that David had given her twenty-six years ago. It was lost; she had thought that it was lost. That Liston had donated the dictionary in which it had been housed.

“My God,” said Ada, and instinctively she reached for it, as if reaching for her father.

“I found it while I was going through the house,” said Gregory. “Packing to leave.”

“Where was it?” she asked.

“The attic,” he said.

“How did it get up there?” she asked him, and he told her he didn’t know.

It had been many years since she had held a floppy disk. Even longer since she had held this one, the original, which she had years and years ago stashed away for safekeeping, working only from copies after that. This one was a five-and-a-quarter-inch disk — an obscure link between the eight-inch disk and the more famous three-and-a-half-inch disk — that just happened to be the standard format for saving data when David had created it. It was enclosed in an opaque white clamshell case, For Ada scrawled in black permanent marker across it. She opened it. Inside was the disk itself, made of matte black plastic. A sticker with the brand name, Verbatim, was affixed to the upper left corner. The upper right corner was the one with the label. There, too, was David’s familiar handwriting, which felt, as always, like a punch to the gut. It had been so long since she had seen it.

Dear Ada, it said on the label. A puzzle for you. With my love, your father, David Sibelius.

“I put it into an ancient disk drive and opened it,” said Gregory. “But the file was corrupt.”

Ada was distracted. She put a finger up to the inscription.

“So no one’s solved it,” said Gregory.

Ada shook her head. She looked at him. In his face she recognized an old glint of the self-satisfaction that had annoyed her as a child, but now it gave her hope.

“Do you have the encryption memorized?” he asked.

“Yes.”

“I thought you would,” he said. “Here. Write it out.” He fished in his pockets once again, produced a pen, pushed a napkin across the table at her.

She wrote:

DHARSNELXRHQHLTWJFOLKTWDURSZJZCMILWFTALVUHVZRDLDEYIXQ.

Gregory took the receipt back. Studied it. A light moved across his face.

“Do you have any ideas at all?” Gregory asked.

“Not really,” Ada said. “The consensus is either that David wasn’t in his right mind when he created it, or that he made it using a one-time pad.”

And as she said it, she lifted from the table the floppy disk Gregory had brought her. She studied it.

It had been years since she had broken an encryption, but she still recognized the buzzing, electric feeling of being on the cusp of undoing one — she had first felt it as a child, with David next to her, guiding her — and it overtook her now. She felt light-headed.

“Do you see it?” said Gregory.

There were fifty-three letters in the encryption.

DHARSNELXRHQHLTWJFOLKTWDURSZJZCMILWFTALVUHVZRDLDEYIXQ

There were fifty-three letters in the message David had written to her, on the label carefully affixed to the original disk:

Dear Ada. A puzzle for you. With my love, your father, David Sibelius.

So there it was, at last: the one-time pad that Hayato had guessed might exist. Without the original disk, without the label stuck to it, the copies they had all been working from were meaningless. The encryption, without its key, was an orphan.

From there, it took them ten minutes to decrypt the rest. Gregory’s eggs arrived. He let them go cold.

“Everything okay?” asked the puzzled waitress, but they barely looked up.

They assigned each letter in the encryption its logical number—4 for D, 8 for H, 1 for A, 18 for R, 19 for S, 14 for N—and from each subtracted the numerical substitute for the letters in the message on the label: 4 for D, 5 for E, 1 for A, 18 for R, 1 for A, 4 for D.

4 minus 4 was 0.

8 minus 5 was 3.

1 minus 1 was 0.

18 minus 18 was 0.

19 minus 1 was 18.

14 minus 4 was 10.

0, 3, 0, 0, 18, 10 translated to nothing obvious at first: it looked something like _ C _ _ R J.

“Try shifting every letter up to the next one,” said Ada. And _C_ _ R J suddenly became ADAASK.

They continued to work until, at last, the whole decrypted message sat before them on the screen, unpunctuated and abrupt, a telegraph message sent to them from twenty-six years in the past.

ADA ASK ELIXIR WHO IS HAROLD WITH LOVE YOUR FATHER HAROLD CANADY

It was easy to reach Frank Halbert, now the head of the old laboratory at the Bit. His information was public, and they found it quickly online. He answered Ada’s e-mail immediately. Yes, he said; the program’s still running.