"We try the lagoon entrance," he said. "I've an idea. I noticed something last night, when we came in." "Do you want to brief me?" "I'd rather not," he admitted. Deirdre shrugged without resentment. The little craft went sturdily toward the passageway to the open sea. She formed an arrowhead of waves as she moved. She neared the points of land at the ends of the coral formation enclosing the lagoon. Thrawn Island was not an atoll. But the beaches were made of snow-white coral sand. Outside there was clear water for a space and then a reef on which the seas broke. Terry headed the boat toward the open sea. Almost immediately after, there was nothing but the reef and the sea between the boat and the horizon. He slowed the boat almost to a stop, well within the reef's tumult. She swayed and rolled on the surging water. "Stay here," he commanded. "I want to swim out and back." He pulled the sweat shirt over his head. He jumped overboard, leaving Deirdre in charge of the boat. The world looked strange to him when waves rolled by higher than his head. A few times the sky narrowed to the space between wave-crests. Other times he was lifted upon a wave-peak, and the sky was illimitably high and large, and the breaking seas on the nearby reef merely roared and grumbled to themselves. He swam out, away from the land. Suddenly his body began to tingle. He stopped and paddled, analyzing the sensation. One side of his body felt as if the most minute of electric currents entered his skin. It was not an unpleasant sensation. Deirdre, in the small boat, was fifty yards behind, watching him. As he swam on, the tingling grew stronger. He dived. The tingling did not vary with depth. He came up, and he was farther out than he'd realized. He suddenly knew that he'd been incautious. There are currents which flow in and out of lagoons. A barrier of reef affects them, too. Terry found himself swimming in an outward-bound current, which pushed him out and away from the island. Within seconds the sensation in his body changed from a mere tingling to torment. For a moment it was just very much stronger and slightly painful, but a moment later it felt as if he swam among flames. It was unbearable. His muscles were not contracted, as if by an electric shock, but he couldn't control their reflexes. He found himself splashing crazily, trying to fight his way out of the anguish which engulfed him. He went under. His body had taken complete control over his mind, and he found himself swimming frantically, underwater. He couldn't reach the surface. His body tried to escape the intolerable agony in which it was immersed but couldn't. He heard a roaring sound, but it meant nothing. The roaring grew louder. Finally, he did break surface for a few seconds, and he gasped horribly, but then he went under. The roaring grew thunderous, and he broke surface again....