Nightclub singer Larry Todd breaks off his romance with a beautiful showgirl when he realizes that she's the girlfriend of a murderously jealous gangster. While on the run, Larry mistakenly believes he killed one of the mobsters, and heiress Mary Carroll helps him escape the police by smuggling him and his partner Myron to Cuba. Mary has inherited a haunted castle on an isolated island and, ignoring ominous warnings and threats, decides to take possession. While there, the trio hunts for a hidden treasure and encounter a ghost, a zombie, and a mysterious killer.