Time bomb at 50 fathoms: Off Italy's southern coast, two ships collide, and the sunken one at sea bottom has a cargo of 900 drums of toxin. Before the metal barrels disintegrate and release their poisons, a team of experts forms to execute an exhaustive recovery plan to stave off catastrophe. Using the pioneering work of Jacques Cousteau's Comshelf experiments, which demonstrated that divers could live and work efficiently for a significant period of submersion, hundreds risk their lives in a race against a deadly toxic time bomb. Mediterranean, cradle or coffin?: Decades ago, Jacques cousteau found the water of Veyron near Marseilles teeming with marine life. Returning years later, he discovered the same sea floor to be a desert, virtually devoid of fish. Appalled at the ravages of pollution, Cousteau and crew seek scientific weapons to combat the horrors of urban wastes pouring into the Mediterranean. The explorers find that not only is pollution to blame, man's industrial might encroaches upon the sea's most vulnerable point, shallow coastal areas that serve as natural habitats.