 In World War II, during a storm, a small plane crashes in an island between Cuba and Porto Rico, but the pilot James  Mac  McCarthy (Dick Purcell) and his two passengers, Bill Summers (John Archer) and his black servant Jeff Jackson (Mantan Moreland), survive. Bill is in a mission trying to find Admiral Arthur Wainwright (Guy Usher), who vanished in that area. They are lodged by the Austrian Dr. Mikhail Sangre (Henry Victor) in his mansion. The scared Jeff finds that the place has zombies, but Mac and Bill do not believe on him. Later, they find that Dr. Sangre is a spy transferring the knowledge of the admiral and other prominent persons to the zombies.