Margaret Lockwood

Frances Gray

Dane Clark

Bill Casey

Marius Goring

Commandant Anton Razinski

Naunton Wayne

Mr. Hedgerley

Wilfrid Hyde-White

Mr. Luke

Eugene Deckers

Alf

Olaf Pooley

Detective-Interrogator

Gladys Henson

Attendant

Paul Hardtmuth

Priest

Michael Hordern

Lab Director Owens

George Benson

Sandwich Stand Customer

Eric Pohlmann

Joe - the bartender

John Horsley

Customs Officer

Patric Doonan

Customs Man

Jill Balcon

Wardress (uncredited)

Ernest Butcher

Tom - Lab Assistant (uncredited)

Anton Diffring

Officer at Station (uncredited)

John G. Heller

Soldier at Station Check Point (uncredited)

Sam Kydd

Customs Man (uncredited)

Richard Marner

Soldier on Train (uncredited)