Five Little Pigs is a work of detective fiction by British writer Agatha Christie, first published in the US by Dodd, Mead and Company in May 1942 under the title of Murder in Retrospect and in the UK by the Collins Crime Club in January 1943 (although some sources state that publication occurred in November 1942). The UK first edition carries a copyright date of 1942 and retailed at eight shillings while the US edition was priced at $2.00. The book features detective Hercule Poirot investigating five people about a murder committed sixteen years earlier. Caroline Crale died in prison after being wrongfully convicted of murdering her husband, Amyas Crale, by poisoning him. In her final letter from prison, she claims to be innocent of the murder. Her daughter Carla Lemarchant asks Poirot to investigate this cold case, based on the memories of the people closest to the couple. Plot summary Sixteen years after Caroline Crale was convicted for the murder of her husband Amyas, her daughter Carla Lemarchant approaches Hercule Poirot, asking him to investigate the case. When Carla was 21 she was given a letter from her late mother claiming she was innocent, and Carla believes this to be true. She fears that her fiancé will leave her if the truth behind the murder is not uncovered. Poirot agrees to her request. On the day of the murder at the Crales' home there were five other people present, whom Poirot dubs "the five little pigs" – stockbroker Philip Blake, amateur chemist Meredith Blake (Philip's brother), Caroline's young half-sister Angela Warren, Angela's governess Cecilia Williams, and Amyas's painting model Elsa Greer. The police found that Amyas was poisoned by coniine, found in a glass he had drunk from. Caroline confessed to stealing the poison from Meredith's lab, intending to use it to commit suicide. She had brought a cold bottle of beer to Amyas and the police think she had poisoned it. Amyas was having an affair with his model Elsa, which was believed to be Caroline's motive. Poirot interviews the five other suspects and notes that none has an obvious motive. Caroline's half-sister Angela is the only one who believes Caroline was innocent. He assembles them, along with Carla and her fiancé, and reveals that Caroline was innocent but chose not to defend herself because she believed Angela had committed the murder. Although Angela had handled the beer