The Mysterious Affair at Styles is a detective novel by British writer Agatha Christie. It was written in the middle of the First World War, in 1916, and first published by John Lane in the United States in October 1920 and in the United Kingdom by The Bodley Head on 21 January 1921.Styles changed into Christie's first posted novel. It delivered Hercule Poirot, Inspector (later, Chief Inspector) Japp, and Arthur Hastings. Poirot, a Belgian refugee of the Great War, is settling in England near the house of Emily Inglethorp, who helped him to his new life. His pal Hastings arrives as a visitor a