A bottle of poison and mistaken identity are prevalent in this suspenseful play, with a plot that twists and turns and combines laughter with thrills. Vincent is a professional suicide merchant who has been contracted by Walter Bryce. He arrives at the Bryce’s country house and mistakenly assumes that his poison is intended for Walter’s consumption. Eventually it becomes clear that his wife, Celia, is the client … or is she? Why are her suicide letters typed and unsigned? Several attempts to do away with various characters result in multiple poisonings of a rubber plant. Will anyone actually drink the poison?