- Alec Guinness
- Professor Marcus
- Cecil Parker
- Claude
- Herbert Lom
- Louis
- Peter Sellers
- Harry Robinson
- Danny Green
- One-Round
- Jack Warner
- The Superintendent
- Katie Johnson
- Louisa Wilberforce
- Philip Stainton
- The Sergeant
- Frankie Howerd
- The Barrow Boy
- Madge Brindley
- Large Lady
- Hélène Burls
- Hypatia
- Jimmy Charters
- Bystander
- Kenneth Connor
- Cab Driver
- Michael Corcoran
- Burglar
- Michael Corcoran
- Burglar
- Arthur Dibbs
- Detective
- Harold Goodwin
- Parcels Clerk
- Fred Griffiths
- Junk Man
- Lucy Griffiths
- Miss Pringle
- George Hilsdon
- Security Van Driver
- Phoebe Hodgson
- Constance
- Vincent Holman
- Station Master
- Frank Howard
- Police Constable
- Arthur Howell
- Constable
- Anthony John
- Child
- Stratford Johns
- Security Guard
- Frederick Kelsey
- Man in Street
- Evelyn Kerry
- Amelia
- Sam Kydd
- Second Cab Driver
- Anthony Lang
- Bystander
- George Leech
- Detective
- Dan Lester
- Porter
- Aileen Lewis
- Lady Leaving Kings Cross Station
- Edie Martin
- Lettice
- Colin McKenzie
- Constable
- Jack Melford
- Detective
- Robert Moore
- Constable
- Arthur Mullard
- (uncredited)
- Paul Phillips
- Bystander
- Ewan Roberts
- Constable
- George Roderick
- Radio Car Policeman
- John Rudling
- Nervous Man
- Leonard Sharp
- Pavement Artist
- George Spence
- Bystander Near Fruit Barrow
- Peter Williams
- Detective at Parcels Office
- Billy Wilmot
- Bystander
- Neil Wilson
- Policeman
- Charles Wood
- Man in Street
