Sir George and Lady Stubbs, the hosts of a village celebration, hit upon the novel idea of staging a mock murder mystery. In good faith, Ariadne Oliver, the well-known crime writer, agrees to organize their murder hunt. Ariadne is puzzled by the abundance of help she's getting, and her mystery-writer's mind becomes suspicious, so she calls her friend Hercule Poirot for help. What they find is a couple on the brink of divorce, a rich Lord and a dizzy Lady, a womanizing architect, and an old woman who is trapped in the horrors of the past. When the girl playing the "dead" body is really murdered, Poirot realizes that someone is playing the game for real, and he intends to find out who it is . . .