Dirk Pitt, death-defying adventurer and deep-sea expert, is out to the ultimate test as he plunges into the perilous waters of the Pacific Vortex — a fog-shrouded sea zone where dozens of ships have vanished without a trace. The latest victim is the awesome superb Starbuck, America's deep-diving nuclear arsenal. Its loss poses an unthinkable threat to national defense. Pitt's job is to find it, salvage it, before the sea explodes. In a furious race against time, Pitt's mission swirls him into a battle with underwater assassins-and traps him in the arms of Summer Moran, the most stunningly exotic and dangerous toward disaster, onto an ancient sunken island-the astonishing setting for the explosive climax of Pacific Vortex!