Conrad Veidt as Otto Becker / Baron Hugo von Detner

Ann Ayars as Kaaren De Relle

Frank Reicher as Fritz

Dorothy Tree as Miss Harper

Ivan F. Simpson as Professor Sterling (as Ivan Simpson)

William Tannen as Ludwig

Martin Kosleck as Kurt Richten

Marc Lawrence as Joe Aiello

Sidney Blackmer as Arnold Milbar

Moroni Olsen as Brenner

Pierre Watkin as Grover Blaine McHenry

Ernie Alexander as Sailor (uncredited)

Rudolph Anders as Cab Driver (uncredited)

Jessie Arnold as Landlady (uncredited)

Walter Bacon as Spy (uncredited)

Polly Bailey as Fat Woman (uncredited)

Roy Barcroft as Chief Petty Officer (uncredited)

Barbara Bedford as Woman (uncredited)

Arthur Belasco as Detective (uncredited)

Walter Byron as Officer (uncredited)

Baldwin Cooke as Waiter (uncredited)

Hal Cooke as Clerk (uncredited)

Clyde Courtright as Doorman (uncredited)

Stuart Crawford as Commentator (voice) (uncredited)

Jack Daley as Reporter (uncredited)

Mark Daniels as Cab Driver (uncredited)

Cliff Danielson as Youth (uncredited)

Jack Deery as Diplomat (uncredited)

Drew Demorest as Reporter (uncredited)

Harry Denny as Restaurant Patron (uncredited)

Herschel Graham as Reporter (uncredited)

Bernadene Hayes as Rosie (uncredited)

Edward Hearn as Reporter (uncredited)

Robert Homans as 1st Captain (uncredited)

Carl M. Leviness as Onlooker at Departure (uncredited)

Wilbur Mack as Reporter (uncredited)

George Magrill as Thug (uncredited)

Frank Marlowe as Sailor (uncredited)

Charles Meakin as Restaurant Patron (uncredited)

James Millican as Operator (uncredited)

Roger Moore as Messenger (uncredited)

George Noisom as Bellboy (uncredited)

William Post Jr. as Harry (voice) (uncredited)

Paul Power as Restaurant Patron (uncredited)

Christian Rub as Mohr (uncredited)

Buck Russell as Restaurant Patron (uncredited)

Tim Ryan as Officer (uncredited)

Jeffrey Sayre as Restaurant Patron (uncredited)

Charles Sherlock as Detective (uncredited)

Russell Simpson as 2nd Captain (uncredited)

Harry Stafford as Elderly Man (uncredited)

Hermine Sterler as Mrs. Mohr (uncredited)

Tom Stevenson as Headwaiter (uncredited)

Brick Sullivan as Radio Operator (uncredited)

Ray Teal as Officer Graves (uncredited)

Philip Van Zandt as Thug (uncredited)

Roland Varno as Bauer (uncredited)

Duke York as Sailor (uncredited)

Jeff York as Keeler (uncredited)

Joe Yule as Barney (uncredited)

William Bailey as

Margaret Bert as

Joe Gilbert as Submarine Radioman (uncredited)