Three Act Tragedy is a work of detective fiction by British writer Agatha Christie, first published in the United States by Dodd, Mead and Company in 1934 under the title Murder in Three Acts and in the UK by the Collins Crime Club in January 1935 under Christie's original title. The US edition retailed at $2.00 and the UK edition at seven shillings and sixpence (7/6) (approximately and approximately respectively). The book features Hercule Poirot, supported by his friend Mr Satterthwaite, and is the one book in which Satterthwaite collaborates with Poirot. Satterthwaite previously appeared in the stories featuring Harley Quin, in particular those collected in The Mysterious Mr Quin (1930). The novel was adapted for television twice, first in 1986 as Murder in Three Acts, and again in 2010 as Three Act Tragedy. Plot summary Renowned stage actor Sir Charles Cartwright hosts a dinner party at his home in Cornwall. His guests include: Hercule Poirot; psychiatrist Sir Bartholomew Strange; Hermione "Egg" Lytton Gore and her mother; Captain Dacres and his wife Cynthia; the playwright Muriel Wills; Egg's friend Oliver Manders; Mr Satterthwaite; and Reverend Babbington and his wife. When the Reverend Babbington suddenly dies after sipping one of the cocktails being served, Cartwright believes it was murder, though Strange finds no poison in his glass. Some time later, Poirot is in Monte Carlo and hears news from Satterthwaite and Cartwright that Strange died from nicotine poisoning after drinking a glass of port wine, despite there being no trace in the glass. With the exception of the three men, Strange's guests are the same ones who attended Cartwright's party. Both Satterthwaite and Cartwright return to England to investigate the murders. They learn that prior to the party, Strange had sent his usual butler away for two months, and that he exhibited strange behaviour as if expecting something. A temporary replacement he hired named Ellis has since disappeared, with Satterthwaite and Cartwright finding drafted blackmail letters from Ellis in his room. Babbington's body is soon exhumed, showing he too died from nicotine poisoning. Cartwright, Satterthwaite and Egg partner to investigate the deaths, joined by Poirot as a consultant. Each guest has a possible motive or suspicious circumstances surrounding Strange's death, but no connection to Babbington. When Wills is interviewed, she recalls noticing Manders apparently drop a newspaper cutting on nicotine, and that Ellis had a birthmark on one hand; she later