Eric Sykes
— Mr. Groomkirby
Julia Foster
— Sylvia
Peggy Mount
— Mrs. Gantry
Mona Washbourne
— Aunt Mildred
George Cole
— Defence Counsel
Jonathan Miller
— Kirby
Alison Leggatt
— Mrs. Groomkirby
Douglas Wilmer
— Judge
Glyn Houston
— Detective Inspector Barnes
Graham Crowden
— Prosecuting Counsel
Kenneth Farrington
— Stan
Walter Horsbrugh
— Clerk of the Court
Frederick Piper
— Usher
Vincent Harding
— Policeman / Bus Conductor
Tommy Bruce
— Gormless (voice)
Trevor Bannister
— Groomkirby's Co-Worker