Snakes on board an American sub set off a chain of events that ultimately causes the boat to sink to the bottom of the ocean. The surviving crew must devise a rescue plan to free themselves and raise the sub.

An American submarine leaves Tierra Del Fuego, and one of its crew has secretly brought aboard a container full of poisonous fer-de-lance snakes which escape storage and bite key personnel on the submarine, causing an accident that cripples the vehicle so that it drops to the bottom of the Southern Ocean. Worse still, the snakes are still at large on the submarine and complicate the efforts of the crew to escape the sunken vessel.—Kevin McCorry <[email protected]>