Ship's engineer Andrew Braddock (York) and two other men are floating in a lifeboat in the middle of the Pacific following the wreck of the ship ''Lady Vain''. One dies at sea. After seventeen days at sea, Braddock and the other man land on an island, where the other man accompanying Braddock is promptly killed by animals. Braddock is nursed back to health in the compound governed by the mysterious scientist "Dr. Moreau" (Lancaster). Besides Moreau, the inhabitants of the compound include Moreau's associate, Montgomery (Davenport), a mercenary; Moreau's mute, misshapen servant, M'Ling (Cravat); and a ravishing young woman named Maria (Carrera). Moreau warns Braddock not to leave the compound at night.