Cecil Parker
— Arthur Prohack
Dirk Bogarde
— Charles Prohack
Hermione Baddeley
— Eve Prohack
Sheila Sim
— Mary Prohack
Glynis Johns
— Mimi Warburton
Denholm Elliott
— Oswald Morfrey
Jon Pertwee
— Plover
Heather Thatcher
— Lady Maslam
Campbell Cotts
— Sir Paul Spinner
Bryan Forbes
— Tony
Frederick Valk
— Dr. Viega
Charles Goldner
— Polish Man Servant
Russell Waters
— Cartwright
Henry Edwards
— Sir Digby Bunce
James Hayter
— Carrell Quire
Ada Reeve
— Mrs. Griggs
Frances Waring
— Nursie
Judith Furse
— Laura Postern
Frederick Leister
— The Director General
Elwyn Brook-Jones
— Benny Erivangian
Eric Berry
— Tailor's Assistant (uncredited)
Janet Burnell
— Mr. Prohack's Personal Assistant (uncredited)
Ian Carmichael
— Hat Salesman (uncredited)
Anne Gunning
— Actress (uncredited)
Humphrey Heathcote
— Turkish Bath Attendant (uncredited)
Desmond Newling
— Pageboy (uncredited)
Lloyd Pearson
— Mr. Bishop (uncredited)
Stanelli
— Orchestra Leader (uncredited)
Jerry Verno
— Taxi Driver (uncredited)
Sam Lysons
— Club Porter