The Crimson Stain Mystery
In attempting to develop a chemical which would make a person super-intelligent, Dr. Montrose fails and the subjects of his experiments metamorphose into hideous monsters who band together and prey on humans. With the police stymied, a young detective attempts to track down the leader of the group of killers, known only to have a small crimson stain in one eye.
- Genre: Mystery, Horror
- Director: T. Hayes Hunter
- Cast: Maurice Costello, Ethel Grandin, Thomas J. McGrane, Olga Olonova, William Cavanaugh
- Country: United States