Irving Pichel Director Robert Livingston Dr. Lawrence Baxter Actor Grace Bradley Jean Sterling Actor Willard Robertson Inspector "Mac" McDonald Actor Pierre Watkin Kennedy Actor Granville Bates Prof. Rexford Sterling Actor William Newell Andrews Actor Byron Foulger Pete Andorka Actor Wilbur Mack F. J. Thompson Actor Matty Fain Burke Actor Smiley Burnette Jimmy Actor Josephine Whittell Nurse Nelson Actor William Hopper Announcer Actor Nat Levine Producer Sol C. Siegel Producer Endre Bohem Screenwriter Richard English Screenwriter Jack A. Marta Cinematographer Edward Mann Film Editing Eloise Costume Design