Leslie Howard as Stephen 'Steve' Locke

Kay Francis as Elena Moura

William Gargan as Bob Medill

Phillip Reed as Gaston LeFarge

Irving Pichel as Sergei Pavlov

Ivan F. Simpson as 'Poohbah' Evans

Halliwell Hobbes as Sir Walter Carrister

J. Carrol Naish as Commissioner of War Trotsky

Walter Byron as Under Secretary Stanley

Cesar Romero as Tito Del Val

Arthur Aylesworth as Mr. Henry Farmer

Alphonse Ethier as Paul DeVigney

Frank Reicher as Mr. X

Tenen Holtz as Lenin

Doris Lloyd as Lady Carrister

Mary Forbes as Lady Catherine Trehearne

Marina Koshetz as Maria Nikolaievna (as Marina Schubert)

George C. Pearce as Lloyd George (as George Pearce)

Gregory Gaye as Mr. Kolinoff

Paul Porcasi as Count Romano

Glen Cavender as Russian Policeman (uncredited)

Claire McDowell as Woman Saying 'Lenin will Live' (uncredited)