Larry Lawrence (Bob Hope) is a New York City crime columnist, with an expose’-type radio show on which he expounds nightly regarding local criminals and mobsters. He is contacted by mobster Frenchy Duval (Paul Fix) and instructed to meet him at a hotel. While going up to Frenchy’s room, Larry inadvertently gets himself involved in a shooting. He mistakenly believes that he has killed a man, Ramon Mederos (Anthony Quinn), rushes into a room and hides in a large trunk, unbeknownst to its owner, Mary Carter (Paulette Goddard). The trunk is loaded onto a boat sailing to an island near Cuba, where Mary has inherited a castle. Accompanying Larry is his assistant/valet, Alex (William Best). Larry comes out of the trunk and meets Mary, who tells him that the castle she has inherited is rumored to be haunted. Larry offers to be her protector after she receives several anonymous threats. Mary’s old friend, Geoff Montgomery (Richard Carlson) warns Mary to stay on the boat, return to New York and not go to the island, as does the Cuban elder, Parada (Paul Lukas). Despite these warnings, Mary and Larry, accompanied by Alex, leave the ship and row to the island. Once there, they begin to realize that perhaps the warnings were right and the island and castle are haunted. They are accosted by ghosts and a mother and son zombie team (Virginia Brissac and Noble Johnson), and hear voices coming at them from all directions. They find Parada, who is dying. He tells them that he has been stabbed by Geoff Montgomery, and that there is a fortune in a silver mine hidden in the basement of the castle. When they go to the basement, they find the silver mine and also Montgomery. Alex comes to the rescue and defends them by killing Montgomery. By this time, the sun has come up, the island doesn’t look so terrifying anymore and Larry, Mary and Alex leave the island, planning to return to mine the silver.