Maj. John Tarrant
Cedric Harper
Ceil Burrows
Alf Chestermann
McKee
Chief Supt. Wray
Alex Tarrant
Lady Melissa Julyan
Sir Edward Julyan
Bateson
Monitoring Policeman
Mike McCarthy
Jane Harper
Miss Monley
Ilkeston
Margaret
MI5 Man
Hetty
Gen. St. John
Jacques (uncredited)
Shadow (uncredited)
Doctor (uncredited)
M15 Man (uncredited)
Pincus (uncredited)
Secretary (uncredited)
Jeweller (uncredited)
M15 Man (uncredited)
Manageress (uncredited)
Commuter (uncredited)
Tourist (uncredited)
Customs Officer (uncredited)