Riptide

For generations, treasure hunters have tried to unlock the deadly puzzle known as the Water Pit: a labyrinth of shafts and tunnels that honeycombs the heart of a small island off the coast of Maine. Reputed to be the hiding place of pirate treasure, the Water Pit possesses an inexplicable ability to kill those who venture into it, from professionals to innocent explorers. The most comprehensive, high-tech expedition ever assembled has come to Maine and to Dr. Malin Hatch, owner of the island. While the treasure hunters have their reasons for mounting this assault - $2 billion in gold - Hatch has his own motives to join them. For Hatch, whose brother died on Ragged Island thirty years before, the only escape from the curse is through the black swirling waters and bloodstained chambers of the Pit.