Prudence and the Pill

Prudence Hardcastle is on the pill. So is her sister-in-law, but someone has been swapping aspirin for their pills. Is it the teenage niece, the maid, the chauffeur, a lover, Prudence's husband Gerald, or all of the above?

• Director: Fielder Cook
• Cast: Deborah Kerr, David Niven, Robert Coote, Irina Demick, Joyce Redman, Judy Geeson, Keith Michell, Edith Evans