During a visit to childhood friend Edith, retired housewife Hetty Wainthropp discovers that Edith's husband, Frank, has a son by a previous marriage. Hetty decides to turn amateur detective to trace him. When this gives her a taste for detection, Hetty decides to set up a private detective agency.

• Yorkshire Television
• Patricia Routledge
• Tony Melody
• Jimmy Jewel
• Jean Heywood
• Gary Waldhorn
• Gary Halliday
• Ram John Holder
• Jean Kent