Five Little Pigs

Five Little Pigs is a mystery novel by the English writer Agatha Christie, first published in 1942 in the United States under the title Murder in Retrospect. It is one of her books about Hercule Poirot.

Caroline Crale was convicted of murdering her husband, the painter Amyas Crale, by poisoning him, and she died in prison afterwards. The letter she wrote from prison before her death claims that she was innocent of the murder.

Sixteen years later her twenty-one-year-old daughter, Carla Lemarchant, is given that letter, and she takes it to Poirot and asks him to reinvestigate the case. He agrees, and establishes that on the day of the murder there were five other people present in the house: the stockbroker Philip Blake; his brother Meredith, an amateur chemist; Caroline's young half-sister Angela; and two others whose accounts he also has to hear. Poirot calls those five the five little pigs, and what he has to do is solve a murder that everybody, including the court, has already decided the answer to.