SOMETHING LAY AHEAD, dark against the thick blue-green swells.

David Moore reached back and cut the sputtering motor. The sharp, hot sun lay across his bare back and shoulders like a bright tropical jacket. The battered fisherman's skiff slowed, rolled lazily across the next swell, and Moore turned the tiller so whatever was in the water would come up on his starboard side. Squinting from the glare of sun off sea, he reached over the gunwale and brought the object up.

It was another piece of timber - God only knew where it had drifted or been torn from. It was a new piece, though, not yet gnarled and aged by the salt water, and he placed it in the bottom of the boat to examine it. On one side there were the remnants of red-painted letters against a white background. An S and an A. Salty? Sally? Samantha? It was evidently a shard of a boat's transom, perhaps one of the Coquina boats, perhaps one that had drifted from a long way off. He knew the names of most of the island's fishing fleet: Jolly Mack, Kinkee, Blue Lady, Lucy J. Leen, Gallant, a dozen others. This boat had probably been destroyed in some distant harbor or maybe it was one of the unfortunates caught in the teeth of the tropical storm that had screamed across the island three days previously. Some fisherman might have lost his life clinging to this boat, Moore thought, staring at the plank. He didn't want to think about that. It brought up too many bad memories.

He started the motor again and swung the tiller so that the skiff's prow was aimed at a point directly into the opening of Kiss Bottom Reef some forty yards ahead. The sea was still fairly rough, "somewhat jumpin'" as the Caribbean fishermen said, and as he neared the reef passage the swells struck hard against the hull. There was debris all around: more splintered timbers, driftwood that might be worth salvaging, tree branches, roof tiles, even a rusted tin placard that read COLA, BEER, WINE. He had seen it ripped off the front of the Landfall Tavern from his hotel terrace. The sign had spun high across the island roofs and had been tossed in a wild, rain-swept spiral into the sea. As Moore passed through the channel he could see the ragged edges of the reef, stubbled with brown and green coral growths, just grazing the surface. A lot of boats had been torn open by those treacherous devil's-horns, and had had to be dragged off to be patched up at the island's boatyard or to die in deeper water. Outside the reef were two "clangers," brightly painted orange buoys that banged and rattled as they were jostled together by the rough currents.

Moore steered between them, following the path of blue-green water before him, and then he headed toward the deeper, almost purple sea in the distance. It was still shallow just off Kiss Bottom - thirty to thirty-five feet - but the sand and coral bottom quickly shelved off into what was respectfully and fearfully known as the Abyss.

Moore turned in his seat and glanced back at the island he'd just steered from to get a correct bearing. The dark, tire-lined piers, the fishermen's cluster of tinderbox shanties, the village of Coquina with its houses and shops of stucco brilliantly painted in wild reds, oranges, pale pinks, blues, browns, light greens. In the white sunlight the colors were dazzling. He let his eyes move up the island, where High Street left Coquina village and wound its way, on a path of ruts and gravel, to a small dark-blue structure with a white gabled roof and white wrought-iron terraces overlooking the harbor. The Indigo Inn was his hotel; he'd made the purchase three years before from an elderly man who was moving back to the States. In the last few days Moore and Markus, his handyman, had been busy replacing broken windows, shattered porch railing slats, and shutters that had been ripped away by the high winds. They did a patchwork job replacing things that had been broken before and would surely be broken again. In the islands, decay was the only certainty.

He turned out from land and steered toward the deeps, searching the water around him. Most of the debris had been washed ashore in the previous few days and whatever was still usable had been gathered up by the islanders. The storm had been a particularly fierce one even for September, one of the most furious of months during the autumn hurricane season. It had blown in from the east, almost unheralded except for the ominously yellow sky. Smashing first into the Coquina harbor, sending boats flying against the piers, the storm had torn a few of the fishermen's dwellings to pieces, then screamed into the interior jungle, uprooting palms and shrubs, and miraculously veered around the shanty village of Caribville on the island's northern point before finally heading out to sea again. The few radios that were the island's sole method of communication had been knocked out by electrical interference. It was a wonder there had been so few serious injuries: only a few broken bones and lacerations, which had been tended by Dr. Maxwell at the clinic.

The sea darkened under his boat. The squat stone tower of the Carib Point beacon lay over his shoulder, a sighting point still used on stormy, wild nights to aid merchant freighters out in the channel. Since it lay near the Carib settlement, it had been allowed to fall into a state of near-ruin. Moore corrected his course a few degrees. In another few moments he was in the right spot; the beacon was just over his left shoulder and the tin-roofed structures of the boatyard drydock shelters over his right. He cut the motor, went to the bow, and heaved a lightweight grapple anchor over the side, allowing the rope to coil out from a hand-winch reel. When the line stopped, he knew that he'd been correct; he was in about fifty feet of water, at the very rim of the Abyss, where the bottom suddenly dropped off into infinity.

Moore moved back to get his diving gear and tank in the stern. He sat down, almost comforted by the skiff's slow rocking, and took off his khaki slacks and thongs. He wore dark-blue bathing briefs underneath, and he pulled a thin cotton T-shirt over his shoulders to guard against strap-burn. When he'd turned on his tank's air supply, he hoisted the tank to his shoulders and strapped it on securely. Then he looked out across the Abyss.

In the distance he could see the faint shapes of far-off land masses: Chocolate Hole, Sandy Cay, Starfish Cay. They were much smaller than Coquina - mainly long spits of hot, palm-edged beaches - and of the three nearest, only Chocolate Hole was really a village. It was a tiny settlement of only fifty or so people who made their living selling green sea-turtles to the bulky industry boats that dealt in local island products. Here, out in the open, the breeze was strong and warm on Moore's face. He let his eyes wander the plain of purple water above the great depths.

Only a few fishermen sailed here; they generally stayed nearer Coquina or fished for albacore and jacks in the shallow waters to the south. The Abyss was a haunted place, so the old islanders - the superstitious ones - said. A score of them had sworn they'd seen or heard things out here. There were those who'd been vehement: a great blazing ghost freighter, burning with a spectral emerald fire, in the midst of the Abyss, water hissing all around her, the moans of her doomed crew carrying out into dawn's twilight. Though Moore was a man who made up his own mind about such things, he was sometimes inclined to believe it wasn't just bad rum or Red Stripe beer talking. Not from the looks some of those men had in their eyes.

But now, in the clear afternoon sunlight, with the entire sky a huge unbroken canopy of hot blue, he could not believe in ghosts. At least, not sailing the surface.

When Moore looked into a mirror, he saw first his father's eyes, as blue as the Caribbean depths themselves, crackling with intelligence and caution. He had let his beard grow when he reached the islands from Europe, and by the time he'd stepped off a tramp steamer onto Coquina's shore he was a hard-muscled, tanned, and lean figure with black hair that curled around his collar, and a dark beard and mustache. He would be thirty-four in November, but he was light-years away from the life he'd led in Baltimore, his birthplace. No one in Baltimore - no one who remained in the life he'd left behind - could have recognized him, except perhaps by his eyes. He was a different man entirely, no longer the one who'd been a rising young executive in his father's bank; who'd lived in a modest if expensive home in a fashionable Baltimore suburb with his wife, Beth, and eight-year-old son, Brian; who'd fought for a membership at the Amsterdam Hills Country Club; who'd owned a beautiful, teak-decked sailing sloop, custom-built by a Canadian firm, that he and Beth had christened - with champagne and all - Destiny's Child. In those days he had worn "the uniform," dark-blue or gray suits with regimental-striped ties, to quiet business luncheons and discussions in oak-paneled drawing rooms where he had struggled to stifle his yawning and restless unease.

He slipped into his black swim fins, strapped a sheathed knife around the calf of his right leg, then secured a weight-belt to his waist. Putting on a pair of gauntlet gloves, Moore rinsed out his mask with seawater, spat into it to prevent it from fogging, and then rinsed it out again. He eased the mask down over his face, put the regulator mouthpiece between his teeth, sucked and exhaled to make certain it was clear, then flipped himself backward over the gunwale in an easy, practiced motion.

Below, in the great room with light-blue walls streaming with sunlight, he waited for his bubbles to clear, watching the rise and fall of the hull above him. When he had adjusted to his underwater world, Moore swam toward the bow, found the taut anchor line and began to follow it hand-over-hand into the depths, his breath appearing before him in crystal globes that ascended to the surface. He went slowly, clearing his ears by squeezing his nostrils shut and blowing every few seconds. In another moment he sighted the bottom, ridges of sand and high walls of tangled coral, and he let go, kicking smoothly away, when he came to the end of the anchor line. Following the bottom, he swam toward the curtain of blue before him, his legs doing all the work, his arms held loosely at his sides. Familiar sights told him he was in the right place: the bulbous mass of brown brain coral that had amazed him the first time he'd seen it; magnificent forest of staghorn coral, now filled with the dart and shimmer of dwarf herring; an angelfish, strikingly blue and yellow, moving gracefully past him.

Through thick clumps of algae that stirred with the currents below, Moore saw a brigade of crabs on the march, freezing solid when they sensed his movement. The reefs were alive; fish flew like birds through the coral openings or whisked themselves into holes to await his passing. The reef dwellers were too accustomed to the predators to take any chances. A shadow covered him, and he looked up. Thirty feet above an eagle ray swam, the wings rippling like beautiful muscle. It vanished into the blue gloom.

Moore had been angling down as the bottom dropped away, and now he faced a wall of gnarled dark coral. He swam through a maze of sea fans, then rose above the wall and stopped abruptly.

Beneath him stretched the Abyss: dark, forboding. The sea turned from blue to black in those depths, like the huge mouth of something waiting to devour him. Though he'd been prepared, the sight of it sent an electric chill through him. Abruptly the vision of the ghost ship, lit by moonlight, glowing green and iridescent, came to him. He brushed it away. If ghosts did exist, Moore thought, they probably were down in that awesome hole. He glanced up at the silvery surface, then thought of the brass ship's compass he'd found last year and began to descend.

There was a freighter down there somewhere, Moore knew; probably so deep his lungs would explode before he could ever reach it. It had gone down sometime in a battle during World War II - that was all he could glean from the stories that floated about the island. Details were sketchy, and no one here really liked to talk about the war. He had gone diving in this area the year before, after another fierce storm, and had discovered a ledge littered with pieces of metal, railings, even the bow portion of a shattered lifeboat. On that dive Moore had found an old ship's compass, the glass missing but the brass still shining. He had taken the compass back to the inn, but when he'd returned to the Abyss a few days afterward the sand had settled back like a flat white carpet, and nothing remained. Another storm had hit soon after, but he hadn't had the chance to dive again, so he'd had to wait for the following season in hopes of finding something else he might be able to salvage.

He continued downward. Where's that ledge? he wondered suddenly, trying to pierce the deep-blue mist. It's dropped away entirely. But then it materialized and he reached it, swimming along a high ridge of rock-dappled sand. There was something metal a few feet ahead: a rusted can. He picked it up. It was still sealed, though badly dented. He let it fall, swam on. In the midst of clumps of coral, probably ripped from the reef at the Abyss rim, there were shards of timber and more cans which gleamed brightly. He held one up and saw himself reflected in the scoured metal. It had been buried. Food supplies for that freighter's crew? he wondered. Maybe. What would be inside? Peaches? Vegetables? He wondered if out of curiosity he should open one to see what was included in a 1942 merchant seaman's diet.

The Abyss stretched down beneath him like the empty socket of a huge eye; there was a series of ledges, all sand choked with rock at various depths, one beneath the other until they faded from sight. One of them, a massive Mt. Everest of sand, caught his eye. It had a definite shape, but he couldn't determine what it reminded him of. Moore descended, intrigued by the mound; he hadn't noticed it before, but then his attention had been on an upper ledge, not the lower ones. He was perhaps ten feet above it when he realized something was protruding from the mass of sand and rock; his heart began to beat more rapidly.

Moore hovered over it, fanning the sand back with quick motions of his fins. The top of a cylinder of some kind protruded vertically. He felt it gingerly. Iron. Unmarked by marine growth, the object, like the cans, had been completely covered over by sand. There was glass in it, very heavily scarred. What in God's name? he wondered. He reached down and pulled at it, only half-expecting it to come free; it wouldn't budge. Moore began to dig the sand away from the object, then wrenched again at it. No use, David old cock, he told himself. This - whatever - is stuck tight. He checked his wristwatch. Time to head for the surface. But this cylinder: the scars of sand abrasion glinting, the glass inset. Fascinating as hell. It could be something worthwhile, he thought. Or perhaps...he gazed down at the sand stirred by his every movement.

Or perhaps something was buried beneath it.

Moore unstrapped his knife from its sheath and dug rocks away from the cylinder's base. He uncovered more iron, gleaming and pitted, an inch at a time. Digging in wrist deep, he pulled the sand away in handfuls. He pried the rocks loose with his blade and let them roll off into that deep hole below him. Another glance at the watch. Time to go! But he was functioning like a machine now, digging and lifting, slowly uncovering what appeared to be a thick, gleaming iron support for that cylinder. There were no growths; it had been buried here for a long time. His knife scraped across flat rock and he shifted his digging to another section.

And then he froze. Forgot to exhale, then exhaled, the bubbles rattling toward the surface over a hundred and fifty feet above.

He had heard something, muffled and far away, like iron being hammered underwater.

Moore waited, his heart pounding, but the noise didn't come again. What was it? He looked around and then realized something very odd: he hadn't seen any fish at this depth. Very odd, in waters teaming with snapper, grouper, jacks, albacore. Moore glanced up, looking for the reassuring distant glow of the sun. There were remnants of jagged rock hanging over him, as if what had once been a ledge just above had given way. He tried to quiet the inner voices. Get to your boat, they whispered. Something is wrong here.

Where were the damned fish?

He continued digging, lifting out coral clumps.

The sand completely obscured his vision, like the roil of white clouds; it had to be extremely deep here, he thought. A mountain of sand and below him the valley of darkness. He plunged in his hands, the fingers closing around a rock, and pulled it out from the mound. When he did, sand cascaded in sheets off the sides of the mountain and on into the Abyss.

Then Moore saw something exposed a few feet away from the strange cylinder and the iron tower. He pulled at the new object. It was a large barrel of some kind, also made of scarred, dented metal. He freed it and it began to slide down the sand slope, and as he clung to it he saw the detonation cap of the device, and the chill of fear raised hair on the back of his neck.

It was an unexploded depth charge.

Moore wrenched his hands back as if they'd been burned. His tank clanged sharply against coral debris, and he fought his way up the mountain away from it, his fins churning water. He could see himself turned inside out by the thing's blast, his body reduced to a mass of bloody shreds. Then the predators would come, and there would be nothing left. He half-sank into the sand, fought himself free in a blinding mist, looking back over his shoulder to see the forgotten charge pitch off the ledge. Then it began to fall into the depths, spinning end over end. Moore reached the summit; the charge had vanished into the dark mists and he stared fearfully after it, praying that if it did explode it would go off hundreds of feet below, where the shock might not kill him. Otherwise...

And then there was a burst of white light far below. The shock came roaring out of the depths, an undersea whirlwind that reached inside him, through the flesh, gripping the bones and twisting.

He gritted his teeth against the pain and roaring noise that almost shattered his eardrums; a fissure split open in the sand, releasing a pulsating globe of air that tore past him and rocketed up toward the surface. The blast echoed all around, the water crazily shifting in all directions, trying to rip him to pieces. The sand parted, cracked open in a dozen seams. It slid under him; an avalanche of it covered Moore and he fell backward, toppling toward the wild Abyss, his tank slamming against coral. Great bubbles of air were roaring all around him, some of them ripping their way free of the sand. Something struck him like the blow of a fist; his mask was torn from his face and the water blinded him. When he felt for a grip, frantically, his hands closed around a solid object. He held on, the currents twisting at him, the noise a throbbing pain at his temples. And then a realization came to him that almost caused him to shout out in terror: he was rising.

There was a shudder beneath him, and through the blue-green distortion he saw a dark, massive shape towering above him. His lungs were filling; he was rising too quickly. He let go his grip and kicked out with his fins against a hard surface that slid past him. He was thrown away from the thing, twisted and turned and mauled by the fierce currents, lost in the explosion of sand and sea. When he could see again he was looking toward the surface into the sun.

Or where the sun had been.

For now it was obscured by the huge shape; the thing was rising to the surface, trailing sand; its shadow covered him, and he felt lost in its darkness. He watched it, eyes stinging. The shape broke through the surface in a roil of foam, and through the ringing in his ears he heard the thunder of sea surging against iron. It hung there, rocking slowly from side to side.

Get up! Moore screamed to himself. No, no. Control. Control. He swam furiously out of the thing's ominous shadow and began to stroke very slowly for the top. He had been thrown almost to the rim of the Abyss, and he concentrated on following the slope of the shelving bottom. He found his anchor line, pulled the anchor free and began to climb. He stopped for decompression at ten feet, watching the hull of his skiff being battered by the waves. When his head finally broke water, he spat out his mouthpiece and hung on to the skiff's gunwale, staring at what lay not more than thirty yards from him.

"Dear God," he whispered.

Its hull was over two hundred feet long; red sunlight had settled into splices in the iron flesh, like the bleeding wounds of a giant saurian. Water foamed around a sharp, evil-looking prow. Remnants of an iron railing hung twisted over the side, partly submerged; there were long dents and gashes in the superstructure and in the bulwark of a conning tower. Moore could hear the sea hissing against its sides.

A submarine.

One of the old World War II types, with a flat deck and a hungry-for-battle look about it. It seemed to be a monstrous predator reawakened, eager for prey.

Moore hung from the skiffs gunwale, unable to think what he should do. And as he watched, he saw the bow of the thing begin to turn. The currents had it now, shoving against its mass. Alive again, the submarine began to move slowly and inexorably toward the island of Coquina.