"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 was Christie's first published novel, introducing Hercule Poirot, Inspector (later, Chief Inspector) Japp, and Arthur Hastings. The story is told in first person by Hastings and features many of the elements that have become icons of the Golden Age of Detective Fiction, largely due to Christie's influence. It is set in a large, isolated country manor. There are a half-dozen suspects, most of whom are hiding facts about themselves. The book includes maps of the house, the murder scene, and a drawing of a fragment of a will, as well as a number of red herrings and surprise plot twists.