Murder in Three Acts

Murder in Three Acts is a mystery novel by Agatha Christie, first published in 1934. It is one of the Poirot novels of the period when Christie was at her most productive.

The book begins with a social occasion and a superstition. Sir Charles Cartwright allows thirteen guests to sit down to dinner and one of them dies at the end of the evening, apparently poisoned by a cocktail that on analysis contains nothing toxic. Poirot's response is characteristic: he remarks that the death was entirely predictable, and then finds that the obvious explanation has no motive behind it. Poirot is on the scene when the death happens rather than arriving afterwards, and his remark that it was predictable is the first clue the reader is handed.

That combination, a death that is legible and a crime that cannot be accounted for, is the engine of the book. The title refers to its structure and was adopted for the American editions; the novel had earlier appeared in the United States under a different title, which is one of several Christie titles whose names were changed between countries in this period.