The Mysterious Affair at Styles is a detective novel by Agatha Christie. It was written in the middle of World War I, in 1916, and first published in the United States in October 1920 Styles was Christie's first published novel, introducing Hercule Poirot, Inspector (later, Chief Inspector) Japp, and Arthur Hastings. Poirot, a Belgian refugee of the Great War, is settling in England near the home of Emily Cavendish, who helped him to his new life. His friend Hastings arrives as a guest at