Scared Stiff: Nightclub singer Larry Todd breaks off his romance with a beautiful showgirl when he realizes she's the girlfriend of a murderously jealous gangster. While on the run, Larry mistakenly believes he kills one of the mobsters and is helped to escape police by heiress Mary Carol, who smuggles Larry and 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 hunt for a hidden treasure and encounter a ghost, a zombie, and a mysterious killer.