Sailor Bob Sherman has his hands full trying to save the ocean yacht Bonito from capsizing in hurricane waters off Venezuela's coast— no thanks to the know-it-all attitude and incompetence of the vessel's captain. Sherman's rugged good looks and seafaring skills at least bring him the attentions of Phyllis Marmion, a raven-haired beauty and daughter of the yacht's owner. Unfortunately, Sherman's also the bitter enemy of the girl's father who, with the support of corrupt officials, had stripped him of a highly profitable drilling business and taken his land years before. More's at stake than oil fields when the ship is attacked by modern pirates and are all taken captive. Soon Sherman, crew and passengers find themselves in a dungeon jail on an uncharted island known locally as the Island of Death— a place where no one escapes, and Sherman's futile efforts have marked him for an early death.