The Narrow Margin is a 1952 American film noir directed by Richard Fleischer and written by Earl Felton, based on an unpublished story written by Martin Goldsmith and Jack Leonard. The screenplay by Earl Felton was nominated for an Academy Award. The picture stars Charles McGraw, Marie Windsor and Jacqueline White. It was released by RKO Radio Pictures. A police detective plays a deadly game of cat-and-mouse aboard a train with mob assassins out to stop a slain gangster's widow before she can testify before a grand jury.