 Squadron Leader Gerry Burton is sent to a tranquil country village to recover from the effects of a plane crash and be nursed back to health by his beautiful sister Joanna. As they are new to the community, they are shocked to receive an anonymous, sexually explicit poison pen letter. They later find that other village gentry have been victimized by the same crank writer, and the vicar s wife sends for her friend Miss Marple in hopes of exposing the perpetrator. When a solicitor s wife apparently takes poison after receiving a particularly vicious message, Miss Marple suspects that the letters are a smokescreen for something more ominous. When a house maid is found bludgeoned to death, she knows she is right.