A string of murders is committed by a killer who seems obsessed with the nursery rhyme “Sing a Song of Sixpence.” Even Miss Marple’s former housekeeper falls victim.

When Miss Marple (Julia McKenzie) learns of the deaths of businessman Rex Fortescue, his young wife, Adele, and their housemaid, Gladys, the circumstances vividly recall the nursery rhyme "Sing a Song of Sixpence." Since Miss Marple had trained Gladys herself, she has a personal reason to investigate. Will her reasoning and deduction make sense of the rhyme and at last reveal the culprit?