Cast
Don Beddoe
Ship's Chief Engineer Anderson
Alan Baxter
Larry Perrin, alias Larry Ross
Jessie Busley
Mrs. Mudge
Erwin Kalser
Dr. Adolph Behrens
Melville Cooper
Ship's Mate Penney
Norbert Schiller
Submarine First Officer
Marjorie Gateson
Mrs. Winslow
Francis Pierlot
Professor Mudge
Bruce Bennett
Ship's gunnery officer
Pat O'Brien
Mike Farrough
Edgar Buchanan
Charles Atterbee
Dick Rich
Perrin's Henchman at Dock
Douglas Gordon
Ship's Lookout
Constance Bennett
Christine Blaine
John Halliday
John Morgan
Stanley Logan
Captain James P. Hollister
Wyndham Standing
Man
Frank Sully
Tommy Malone
Olaf Hytten
Agent
Frank Baker
Detective