Pat O’Brien
Mike Farrough
Constance Bennett
Christine Blaine
John Halliday
John Morgan
Alan Baxter
Larry Perrin, alias Larry Ross
Erwin Kalser
Dr. Adolph Behrens
Edgar Buchanan
Charles Atterbee
Frank Sully
Tommy Malone
Marjorie Gateson
Mrs. Winslow
Francis Pierlot
Professor Mudge
Jessie Busley
Mrs. Mudge
Melville Cooper
Ship's Mate Penney
Stanley Logan
Captain James P. Hollister
Leslie Denison
Ship's Mate Jones
Don Beddoe
Ship's Chief Engineer Anderson
Norbert Schiller
Submarine First Officer
Frank Alten
Submarine Radio Operator
Bruce Bennett
Ship's gunnery officer
Rex Post
First Mate
Dick Rich
Perrin's Henchman at Dock
Olaf Hytten
Agent
Arthur Mulliner
Detective
Frank Baker
Detective
Frank Benson
Sailor
Bobby Hale
Sailor
Fred Wolff
German Sailor
Douglas Gordon
Ship's Lookout
Jean Prescott
Mrs. Hollister
Hans von Morhart
German Sailor
Paul Michael
German Sailor
Wyndham Standing
Man
Arno Frey
Submarine Gunner
David Dunbar
Sailor
James Kilgannon
Sailor
Hans Schumann
Submarine Commander