Simon checked his depth gauge: the arrow lay just a hair to the far side of the 130 mark. Even at this depth he was comfortable in a 1.5-mm dive skin.

He looked around. The light level was decent, typical for this depth, though the true colors of the fish and coral were washed out. Sunlight's spectrum got pretty well bleached out after struggling through 130 feet of water.

He'd hoped he'd be diving the cavern through the bore hole, much like descending the limestone cenotes in the waters of the Yucatan, but the hole was too small and there was no hope of widening it any further. So he went hunting for the natural entrance to the cavern. He found it, a dark, narrow, anemone-fringed opening in the wall of a rift in the continental shelf. The wall was encrusted with sponges, guzzling the fringe of the Guyana Current as it swept nutrients up from Venezuela's Orinoco River.

Simon also found the missing diver, Abdul. A rock the size of a Porsche Boxster - loosened by the drilling, perhaps? - had slipped from the wall above the opening and crushed him. The crabs and yellowtails had been snacking on his exposed flesh, but his mask was still fastened around his head, sparing his wide-open, milky eyes. Their empty gaze brought back a few lines he'd just read inThe Tempest :

Full fathom five thy father lies;

Of his bones are coral made;

Those are pearls that were his eyes....

Simon shuddered and looked away. A sight like that could make you believe in the Obeahman. Empty sockets would have been better.

The stone had also partially blocked the mouth of the entrance. The opening that remained might admit a child but never an adult, especially one of Simon's girth.

Which meant the stone had to be moved. And since the local labor pool consisted of himself and one curious green sea turtle, that meant it was up to him.

After a thorough inspection, he found a spot where he could wedge himself between the rock and the rift wall. It meant disturbing some sponges and dislodging some of the smaller clinging sea life, something Simon loathed doing. The Caribbean reefs took enough abuse without his adding to it.

But he had no choice.

With knees bent almost to his chest, his flippers against the rock and his back against the wall, he took a deep breath and kicked out with everything he had. After half a minute of straining, he felt the rock move. Heartened, he found a little extra strength and increased his effort.

Slowly, moving a fraction of an inch at a time, the rock began to tilt away from him. Simon squeezed shut his eyes and, shouting into his regulator's mouthpiece, pushed even harder.

And then he stopped, gasping as a crushing weight slammed against his chest. He opened his eyes and wouldn't have been surprised to find that the rock had fallen back on him, pinning him to the wall. But no, the rock was falling away, tumbling end over end in slow motion toward the floor of the rift. The pain was coming from his heart. He could feel that battered old pump pounding out an irregular beat, thudding in his ears as his vision wavered.

He slowed his lungs, taking deep, measured breaths, hoping his heart would follow suit, and cursing himself for being so careless as to have left behind his backup nitros, the fast-acting sublingual tablets for when his angina broke through the extended-release pills.

As he prayed for the pain to ease, proving this wasn't the Big One, motion to his left caught his eye.

Abdul, free of the entrapping rock, was pulling away from the wall and gliding toward Simon. His face came closer, his dead wide eyes staring into Simon's as if to say,Join me...Join me ....

With his face close enough to kiss, Abdul turned away. His bloated body began a slow ascent, belly first, arms and legs dangling behind, returning at last to the world of air and light it had departed.

Just as slowly, the crushing weight lifted from Simon's chest. His heart slowed. Just angina. A bad attack, but the 40 percent oxygen in his tanks had helped.

He pushed away from the wall and stared at the now wide-open passage into the cavern. No way. Not today. He didn't have the strength. He'd make up an excuse for Frikkie, tell him about the stone, tell him he'd used up too much daylight moving it, tell him he'd finish the job tomorrow under the high morning sun, tell him anything except the truth about his heart.

Not that his health would prompt Frik even to consider calling off the dive.A shark bit off your left leg? So? The right one still works. Get back down there and find me that fifth piece!

No, it was no one else's business.

Tomorrow. Tomorrow he'd find Frik's damn doodad with no problems, no complications.

Right now what he needed was a drink.

Weak, tired, and perhaps even a little depressed, Simon shot a bolus of air into his vest and began a controlled ascent.