A Knife Edge

Prologue

The shark's back was the width of a boardroom table and crosshatched with countless battle scars. It cruised a foot and a half beneath the surface, dorsal fin knifing the oily blue swell above. There was little apparent caution in the way it meandered back and forth alongside the Natusima. If the cook didn't know better, he'd have said it seemed to be waiting for something. The inevitable theme music from the movie Jaws playing in his head, he took a final drag on his cigarette, then flicked the butt into the water. He glanced left and right and, satisfied the coast was clear, motioned at the kitchenhand to tip the pot containing what was left of last night's stew over the railing. The pot was heavy and the young man grunted with the effort required. The cook knew he was risking his job. The damn tree-huggers aboard ship would have his balls if they found out about this. “Don't feed the animals,” one of them had said when someone had suggested throwing scraps to the shark. All the other guy wanted was to bring it in close to get some cool snapshots for the wife and kids.

“Now, that there's a goddamn fish,” the cook said to the kitchenhand as he lit another Chesterfield and watched the shark glide past with its mouth open.

“Fuckin' A,” agreed the young man.

The massive shark broached as it turned back toward the splash made by the stew hitting the water, displaying multiple rows of white teeth set in red, pulpy gums. But then the fish appeared to change its mind, resuming its original course. It circled back for a pass beyond the stern, trailing a wake like a boat with an outboard motor. The cook experienced the cold realization that the brute seemed more interested in the meat moving around up behind the railing and beyond its reach — namely him—than it was in the chuck steak sinking slowly into the depths. Confirming this, the shark appeared to fix him with its ancient and fathomless black eye.

The kitchenhand muttered, “Fuckin' thing gives me the creeps. Why the hell are we feeding it, anyway?”

“So we can tame it. Maybe we can teach it to roll over,” the cook said.

The kitchenhand gave his boss a look that said, Are you serious? He found his boss's preoccupation with the thing freaky. He tugged the zipper on his jacket up to his chin and clapped his gloved hands together. It was getting cold, or perhaps it was the company that gave him a chill.

The cook found himself wondering what it would be like to be down there in the water alone with that fish, helpless. The skin on his arms prickled with goose bumps. What would it be like watching a man being mauled by it — how long could you last? Now, that would be some entertainment, he thought.

The shark had appeared two days earlier, trailing the ship. A veteran seaman claimed the animal had been following them for far longer as they motored up the Japan Trench.

The man-eater's presence had excited much interest at first — it was the biggest shark anyone had ever seen — but that had waned as the scientists and submersible specialists readied and then launched the Shinkai. There was some concern about what the beast would do when the deep-diving craft entered the water, but in fact the meeting between the two was a nonevent. The sub was over thirty feet long, barely ten feet longer than the great white, and it bristled with many delicate sensors and remote-operated arms, any and all of which could easily be damaged by the shark if it became inquisitive. It did indeed approach the sub, but then turned away with a flick of the tail, snubbing the vessel, much to the relief of the scientists.

The recovery ship, Natusima, was “anchored” in a relatively shallow part of the 29,500-foot-deep trench, thrusters linked to its navigation systems keeping the ship stationary above a point on the seafloor. The Shinkai had been down for over six hours already, diving on hydrothermal vents at the very extremity of its 21,000-foot performance envelope.

At a depth of 20,374 feet, the world outside was solid black, so utterly black it seemed almost to suck the very illumination from the Shinkai's spotlights. Weird and delicate creatures in all their phosphorescent glory curled, snaked, drifted, or darted past the submersible's portholes, indicating that this blackness was in fact teeming with life, and was liquid rather than solid.

“Back us up a tad,” said Professor Sean Boyle.

Dr. Hideo Tanaka's thumb shifted a toggle on the hand controller. There was the slightest vibration accompanied by an electrical hum and the Shinkai's twenty-six tons eased away several feet from the volcanic rock face. Darkness rushed in to fill the widening gap.

“That's it,” said the professor. He watched one of the video screens, leaning toward it with intense concentration.

“You OK about going down again?” asked Tanaka, a little concerned about his research partner's well-being.

The professor nodded. Perspiration dripped from his forehead onto his sweat-soaked T-shirt.

The technician handling the buoyancy controls made the adjustments and the sub slid horizontally into the depths. The hull popped a couple of times. Outside, the pressure was close to 630 atmospheres. If a seal gave out now, even a thin stream of water under such pressure would slice through the three men inside like a wire through soft cheese. Professor Boyle was aware of the danger and it weighed heavily on his mind. Dr. Tanaka had spent a lot of time in deep-sea submersibles over many years and experience had taught him this fear — a kind of claustrophobia — was irrational. These submersibles were overengineered and the Shinkai's real limit, before the weight of the sea above the hull crushed it to the thickness of a slice of bread, was probably closer to 23,000 feet.

“Let's get below the smoker,” said the professor reluctantly.

Tanaka agreed. The American-born Japanese nodded at the technician and together they completed the maneuver.

Beads of sweat dribbled into Professor Boyle's eyes while he watched the monitor. The screen displayed what was visible on the volcanic plate just beyond the bow of the Shinkai, as well as providing real-time data for sea depth, current direction and speed, sea temperature, and hull pressure. The temperature, barely 37°F sixty-six feet away, was climbing rapidly as the sub neared the hydrothermal vent.

What had seemed to be bare rock gradually became a meadow of enormous pale yellow tube worms captured in the Shinkai's lights. The tube worms, each over a yard in length, swayed in the gentle convection current. A movement at the corner of the screen caught the scientists' attention. Dr. Tanaka toggled the external camera so that the view in the monitor swept left. A huge white spider crab crawled into view, reminding Tanaka of something from a horror movie. It was gobbling something, long and slender poles ending in claws feeding torn strips of worm into its mouth. “Christ, what a monster,” muttered Boyle.

An angelfish drifted into view as the submersible continued its descent. “Now there's a face only its mother would love,” said the technician. The small fish dangled its glowing lantern in front of a grotesque, lethal-looking underbite, the brutal fangs in its wide mouth poised for the strike. Alarmed by the sound of the sub's motors, the spider crab darted away.

The temperature climbed further as they descended. “Anyone for a hot tub?” inquired the technician.

“Pass,” Boyle muttered, eyes glued to the screen in front of him. The sea temperature had soared to 86°F as the smoker came into view. They were several yards up-current from the volcano that was spewing a plume of black, superheated seawater, hydrogen sulphide, and iron monosulphide into the surrounding sea. By rights, this area should have been devoid of life. There was no oxygen down here, and no light, only boiling liquids capable of stripping the paint off a ship's hull. And yet around the base of the smoker's funnel was a thriving community of life, life that would, perversely, find existence in a more conventional environment lethal.

“Jesus,” Boyle said under his breath.

As far as Boyle and Tanaka knew, this was the deepest anyone had ever dived on a smoker, and here laid out before them was an improbable Garden of Eden. The bed of worms had become denser and the creatures themselves were as big as anacondas. Shrimp the size of house cats darted between the tubes waving in the current. There were more giant spider crabs, and clams so big they looked like footballs. The tube worms and the mollusks had been well-documented phenomena present at other hydrothermal vents at shallower depths, but those were nowhere near as big as the ones here. Strange fish neither scientist had ever seen before hunted over the tube worm beds, chasing smaller fish and shrimp. None of the life bore the usual hallmarks of fish found at this depth — the huge eyes and teeth and the lights swinging from various protuberances. There was so much life down here it was literally bumping into itself.

“Amazing,” Boyle said, awestruck by the information provided by the monitor. It'd been years of theoretical slogging to get to this point. There were moments when they'd been skeptical themselves about finding such a biologically diverse world at — he checked the gauge — nearly 21,000 feet. And yet here it was. This discovery alone would have made them famous, except that their research was classified. The people paying the bills, the U.S. Department of Defense, wouldn't have it any other way.

The technician sitting beside Tanaka tapped his watch. The Shinkai ran on battery power and the needles were leaning toward the red. They had an hour and a half at most before they had to start the climb to the Natusima. Tanaka nodded.

“Let's get to it,” agreed Boyle.The technician turned to another panel and readied the Shinkai's arms. A thin appendage could be seen moving across the monitor, the clawlike hand flexing open and closed, ready to collect specimens. The motion reminded Boyle of the spider crab. And that thought reminded him there was a lot of work yet to be done.

The sea was flat; even the low swell of the past week had rolled onto the Japanese mainland beyond the western horizon. It was night and the Natusima could have been anchored on a lake of black glass. As he stumbled down the gunnel, Dr. Tanaka tripped on a part of the steel deck hidden in deep shadow. He swore under his breath and grabbed the railing to steady himself. He threw his head back to get some air and looked up into the cloudless night sky. The moon reminded him of a polished quarter, one that appeared glued to the Milky Way. The doctor managed to hum a couple of bars of “Moon River” before his stomach gave way, convulsing several times as a torrent of food and alcohol roared out of his mouth and spattered onto the sea below.

Vomiting made Tanaka feel better. He wasn't used to drinking alcohol — Red Bull was about as strong as his drinks got, and he never had more than three. But there was no Red Bull on board, so he'd been convinced to have an inch or two of Johnnie Walker. It was a celebration after all, and Boyle had been insistent. How many scientific quests end in failure? Tanaka didn't know the answer, but he reasoned the percentage would be high. And yet they'd struck gold on the very first day and bagged a huge variety of bizarre specimens. They'd had five days of uninterrupted diving and the hard work was largely done. Tomorrow, they would up anchor and leave, ahead of schedule. The ship's master informed them that the weather was going to turn nasty during the night — they were experiencing the proverbial calm before the storm — so they'd decided to end the expedition early and head for the port of Yokohama. With luck, the sulphide-oxidizing extremophiles they sought for further experimentation would be hiding among the specimens brought to the surface. No, damn the luck! “Luck's for schmucks,” Tanaka slurred aloud, directing his comment at a winch. He and the professor had made their own good luck, and it had paid off in spades.

The celebration in the mess was still going strong, the music leaking through the metal and glass superstructure and up on to the stern deck. Eminem and 5 °Cent were getting a rest. The Rolling Stones song “Sympathy for the Devil” played. One of the older members of the crew must be DJ-ing, Tanaka decided. There was a sudden short spike in the music volume, signifying that a hatch had opened and closed. Someone else had left the party to get some air. Tanaka peered drunkenly into the moonlight. The ship was illuminated by two large spotlights perched high on the crane's cross member, but the light was hard and stark and heavy black shadows thrown by a multitude of gear lay across the decks. “Hello,” Tanaka called, but got no answer. He shrugged. Leaning on the railing, he looked out across the polished obsidian sea, his head spinning a little, his mouth sour.

Suddenly, he felt himself being lifted from the waist. Before he could struggle, he was thrown over the railing. The world spun and a cry escaped his throat before he hit the water and plunged below the surface. The shock of the cold seawater made him gag. He broke the surface spluttering, choking, instantly sober. “Hey, what the fuck?” he shouted, the saltwater searing his throat. “Hey!” The Natusima's black hull reared up beside him, an unscaleable face. He slapped the steel slab with his open hand. “Hey!” There was no reply, although he thought he heard something. Was it a cough? There was a mechanical sound to it. “Hey! Someone there?” There was no repeat of the sound, just the distant beat of music coming from deep within the ship. He dashed the water's surface with his arms in frustration and anger, and kicked off his sneakers so that he could swim better. Phosphorescence swirled around him. “Who the fuck threw me in?” he screamed, the chill of the water like sandpaper rubbing against his skin. No answer. “Hey!” Tanaka's voice echoed back at him, bouncing off the cold steel hull. “Jesus…” he said in frustration, treading water. He peered up into the alternating dazzle and darkness of the ship and thought he saw the silhouette of a man's head and shoulders up behind the railing. “Hey, you!” he shouted. No response. Someone had thrown him in, right? Was it that shadow up there?

Tanaka's heart rate was up, mainly because of the shock of close-to-freezing water, but also because he realized getting back up onto the ship wasn't going to be easy if he couldn't attract someone's attention. He could be stuck out here, but not for long. The cold would soon cramp his muscles and then he'd drown. He knew he had around three minutes, max, before his muscles stopped working and he sank beneath the water. There was no convenient ladder anywhere on the hull — it wasn't that kind of dive vessel. His jeans and sweatshirt were weighing him down, making swimming difficult. He stripped down to his underwear, and noted that the phosphorescence illuminated his legs, accentuating their whiteness. He felt naked, exposed, freezing. His skin was already numb. The realization that there were nearly 30,000 feet of water beneath his feet added to his feeling of exposure. Nearby, he heard the vibration of a thruster automatically keeping the Natusima in position. The ship must be starting to drift, he thought. It turned slowly on its axis, as if moved by a giant and invisible hand, its stern swinging toward him. He swam away to prevent being struck by the hull.

“Hey!” he called out again. “Anybody…!”

The lights on top of the crane that launched and retrieved the Shinkai also lit the water behind the stern. Tanaka swam into the light. He'd be seen for sure now. He yelled out several more times and loaded on the expletives as his frustration grew.

Suddenly Dr. Tanaka felt the pressure wave behind him. And then he swirled into an eddy, which spun him around a couple of times. His mind froze, incapable of grappling with the nightmare finale to his forty-two years on the planet.

The impact of the shark's 2200 pounds drove the breath from his lungs. Its serrated teeth ripped through the flesh of his back, buttocks, and legs, and severed a number of major arteries and veins along with his spinal cord. He screamed and thrashed his upper body, fighting for a life that was already lost.

Bloody seawater streamed through the shark's gills. Its ancient brain had registered the torn, thrashing remains of the wounded animal above it, framed by a spreading pool of blood.

Tanaka felt no pain. In fact, he felt nothing. Everything had shut down, even consciousness. His eyes were open, but unseeing. His mouth was also open but no sound came out. Everything that was Dr. Tanaka was in hiding way down deep, 30,000 feet below the surface. For all he knew, his broken, crushed, and bleeding body was someone else's.

The shark was unintentionally merciful on the second pass. It hit hard and took nearly everything in a single bite, leaving only the doctor's head to roll, eyes hooded in death, bobbing in its wake.

Seconds later, up on the ship, a hatch opened and a shadow stepped inside. The music blared momentarily and then the hatchway clanged shut.