James Mason
Role: Richard Francis Heritage
Joyce Howard
Role: Laura Verity
Tom Walls
Role: Christopher Child
Phyllis Stanley
Role: Lily Bernard
David Farrar
Role: Commander Lippinscott
Karl Stepanek
Role: Riccardo
Walter Crisham
Role: Charlie
Jeanne De Casalis
Role: Lady with Dog
Patricia Medina
Role: Mary, Manicurist (as Pat Medina)
George Robey
Role: Pawnbroker
Ronald Chesney
Role: Max - Mouth Harmonica Player
Finlay Currie
Role: Merchant Captain
Brefni O'Rorke
Role: Detective Inspector Burrows
Eric Mason
Role: Benson - Illusionist
Anthony Holles
Role: Hotel Hairdresser
Kynaston Reeves
Role: Naval Officer in Charge of Court Martial
Herbert Lomas
Role: Van Driver
Percy Walsh
Role: Police Sergeant
Terence de Marney
Role: Code Expert
Charles Victor
Role: Pub Owner
Robert Sansom
Role: Petty Officer Bill Grant
Alvar Liddell
Role: Boothby - Radio Announcer
Anthony Dawson
Role: 2nd Code Expert
Alf Goddard
Role: One of Mansel's Tough Friends (uncredited)
David Keir
Role: Henry (uncredited)
Jack Melford
Role: Defence Lawyer at Court Martial (uncredited)
Hay Petrie
Role: Waiter (uncredited)
Leonard Sharp
Role: Bus Conductor (uncredited)
Dennis Wyndham
Role: George the Barman (uncredited)
