Clark Gable as Philip Sutherland

Gene Tierney as Marya Lamarkina

Richard Haydn as Christopher Wellington St. John Denny

Bernard Miles as Joe Brooks

Anna Valentina as Svetlana Mikhailovna

Kenneth More as Steve Quillan

Belita as Valentina Alexandrovna

Karl Stepanek as Commissar

Theodore Bikel as Lieutenant

Frederick Valk as Kuragin

Peter Illing as N.K.V.D. Man

Robert Henderson as U.S. Ambassador

Stanley Maxted as John Barnes

Meinhart Maur as Lemkov

Alexis Chesnakov as General Zhdanov

Anton Diffring as Hotel Desk Clerk (uncredited)

Martin Benson as Toasting Russian Officer (uncredited)

Anton Dolin as Marya's Partner (uncredited)

Richard Marner as Toasting Russian Officer (uncredited)

Arthur Mullard as Russian Policeman (uncredited)

Jim Brady as Guard at Bolshoi Theatre (uncredited)

Christopher Rhodes as Plainclothes Police Officer at Airport (uncredited)