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.
Patricia Routledge
as Hetty Wainthrop
Tony Melody
as Robert Wainthrop
Jimmy Jewel
as Frank Cross
Jean Heywood
as Edith Cross
Gary Waldhorn
as Bernard Shawcrose
Gary Halliday
as Geoffrey Shawcross
Ram John Holder
as Chalky White
Jean Kent
as Phillida Meadowhite
Janet Allen
as Mrs. Lilium
Andrew Paul
as Photographer
Jenna Russell
as Jan
Julie Foy
as Madge
