Peter Yates Director Eric Sykes Mr. Groomkirby Actor George Cole Fred Actor Julia Foster Sylvia Actor Jonathan Miller Kirby Actor Peggy Mount Mrs. Gantry Actor Alison Leggatt Mrs. Groomkirby Actor Mona Washbourne Aunt Mildred Actor Douglas Wilmer Judge, Maintenance Man Actor Kenneth Farringdon Stan Actor Glyn Houston Detective Inspector Barnes Actor Graham Crowden Prosecuting Counsel, Caretaker Actor Walter Horsbruch Clerk of the Court, Drycleaner's Assistant Actor Frederick Piper Usher, Office Clerk Actor Vincent Harding Policeman, Bus Conductor Actor Norman Frederick Simpson Writer Michael Deeley Producer Denys N. Coop Cinematographer