Boris Karloff as Valdar

Margaret Lindsay as Helene von Lorbeer

Bruce Lester as Frank Bennett

Leonard Mudie as James Yeats

Holmes Herbert as Arthur Bennett

Austin Fairman as George Bennett

William Bailey as British Intelligence Agent

Louise Brien as Miss Risdon - Bennett's Secretary

Glen Cavender as Under Officer Pfalz

David Cavendish as Capt. Lanark

Joe De Stefani as German Officer

Carlos De Valdez as Von Ritter

Clarence Derwent as Milkman

Arno Frey as German Junior Officer

Frederick Giermann as Otto Kurtz

Lawrence Grant as Brigadier General

Carl Harbaugh as German Soldier

Sam Harris as Cabinet Minister

Winifred Harris as Mrs. Maude Bennett

Leyland Hodgson as Lord Sudbury

Stuart Holmes as Luchow - German Soldier

Willy Kaufman as German Corporal

Crauford Kent as Cmdr. Phelps

Morton Lowry as Lt. Borden

Lester Matthews as Henry Thompson

Frank Mayo as Brixton - Intelligence Agent

Paul Panzer as Peasant

John J. Richardson as Cockney Soldier

Ferdinand Schumann-Heink as German Officer

Hans Schumm as German Senior Officer

John Graham Spacey as Crichton - Intelligence Agent

Robert R. Stephenson as Cockney Soldier

Evan Thomas as Maj. Andrews

David Thursby as Agent Reporting Strengler's Identity

Frederick Vogeding as Baron Kuglar

Leonard Willey as Capt. Stuart

Maris Wrixon as Dorothy Bennett

Henry Zynda as German