The Intruder

During a tropical storm, the captain of the S. S. Intruder investigates the brutal murder of a passenger named Gardner, who has been killed with a fire axe. To his relief, the investigation is taken over by Samson, a San Francisco police detective, who says he has been trailing Gardner, a jewel thief, for months. Samson questions Gardner's valet Carlo and five of the passengers whom Carlo says he had seen in contact with Gardner: Jack Brandt, who, according to Carlo, quarreled with Gardner and threatened to kill him; Cramer, a third-class passenger; Mr. Wayne, whom Gardner was blackmailing; Wayne's daughter Connie; and Daisy, a blonde from the suite next to Gardner's. The investigation is interrupted when the ship hits a sunken wreck and must be evacuated. Samson orders the suspects to get into the same lifeboat, along with some crew members, and after Connie realizes her brother Reggie is missing, Jack drags the drunken Reggie from his cabin just in time. The next morning, they land at a deserted island, where they hear the screeching of gorillas and a terrifying human cry. Samson accuses Jack of Gardner's murder because the deceased's gems were found in his room. Connie and Daisy are given quarters in a deserted cave, and when they awaken, they are horrified to find a human skeleton. Daisy tells Connie that Carlo, to whom she admits she was once married, told her that Gardner was blackmailing her father and that Jack threatened to kill him if he ever bothered her or her father. They run into Cramer, with blood dripping from his hand, and he pulls a gun and orders them to walk through the jungle. Meanwhile, Samson spots a ship and the men set off flares. The captain of the Intruder is found dead, and Jack notices that the girls and Cramer are gone. In the jungle, Cramer is about to shoot the girls when a gorilla's scream allows them to escape into a cave, which is inhabited by two skeletons and a wild man, who calls one skeleton "Mary" and knifes the other, whom he calls "Joe," but does not harm the girls. After the ship, a French vessel, comes to shore, Connie hears Reggie call for her and comes out of the cave. Cramer shoots her with his last bullet, then Jack follows him into the cave and they fight. When the wild man tries to stab Jack, Daisy stops him. Cramer gets away, but Samson shoots him. In the cave, Jack picks up a piece of paper Cramer dropped. On board the French ship, the wild man sits next to "Mary," whom he has placed in a deck chair, while Daisy tells Connie, who was only wounded by Cramer, that Jack said some romantic things to her when she was unconscious. After Samson deduces that Cramer must have killed Gardner and draws a map to show how he climbed from the third-class deck to first-class without being seen, Jack reveals that the paper he found in the cave contains a map of the ship that is identical to the one Samson just drew. Samson pulls a gun, but Jack subdues him. Afterward, Jack tells Connie that he cabled San Francisco and then deduced that the man who identified himself as Samson was using the credentials of a detective who has been missing for four weeks and had been on Gardner's trail; Cramer had been his assistant. As Jack and Connie kiss, they are interrupted by gunshots that Reggie, drunk again, is perpetrating.