The first attack occurrs in the underwater caverns of the Bahamas. Two professional divers exploring the unknown. A monstrous flesh-ripping predator they never see coming. Now the attacks are coming closer and closer to shore. A sun-soaked playground for sea-loving tourists. A human feasting ground for whatever lurks beneath. Now, in a desperate race against time, Eric Watson, an expert on remote control underwater vehicles, and marine biologist Valerie Martell must identify a savage new species of killer--and piece together one of nature's most horrific mysteries.