Alastair Sim
— Samuel Blight
Barry K. Barnes
— Larry Preston
Diana Churchill
— Janet Preston
Edward Chapman
— Detective Inspector Bray
Ruby Miller
— Mrs. Honeycombe
Austin Trevor
— Heinreks
Leo Genn
— Another Agent
Geoffrey Sumner
— Detective Delacroix
Glen Alyn
— Agent Posing as Reporter
Torin Thatcher
— Karl Bergsen
Carl Jaffe
— Foreign Agent
Cathleen Nesbitt
— Miss. Sampson
Cyril Smith
— Barber
James Harcourt
— Judge