Val Guest Director, Producer, Writer Jack Warner Det. Insp. Fred Fellows Actor Ronald Lewis Det. Sgt. Jim Wilks Actor Yolande Donlan Jean Sherman Actor Michael Goodliffe Clyde Burchard Actor John Le Mesurier Mr. Simpson Actor Moira Redmond Joan Simpson Actor Christine Bocca Mrs. Simpson Actor Brian Oulton Frank Restlin Actor Ray Barrett Sgt. Gorman Actor Norman Chappell Andy Roach Actor John Barron Ray Tenby Actor Joan Newell Mrs. Banks Actor