Businessman Rex Fortescue dies after being poisoned at breakfast, with rye found in his pocket. Further deaths at the family home appear to follow a nursery rhyme, and Miss Marple becomes involved because one victim had previously worked as her maid.
The investigation exposes fraud, colonial fortunes, resentful heirs and the insecurity of domestic workers in post-war Britain. Miss Marple treats the rhyme as both clue and misdirection, insisting that a servant’s life deserves the same attention as the wealthy family whose conflicts dominate the police inquiry.