Hercule Poirot sort of obsessive-compulsive" in Poirot. As mentioned in "Curtain" and "The Clocks", he is fond of classical music, particularly Mozart and Bach. In "The Mysterious Affair at Styles", Poirot operates as a fairly conventional, clue-based and logical detective; reflected in his vocabulary by two common phrases: his use of "the little grey cells" and "order and method". Hastings is irritated by the fact that Poirot sometimes conceals important details of his plans, as in "The Big Four". In this novel, Hastings is kept in the dark throughout the climax. This aspect of Poirot is less evident in the later novels,
Hercule Poirot away..." At the end, Poirot usually reveals his description of the sequence of events and his deductions to a room of suspects, often leading to the culprit's apprehension. Christie was purposely vague about Poirot's origins, as he is thought to be an elderly man even in the early novels. In "An Autobiography," she admitted that she already imagined him to be an old man in 1920. At the time, however, she had no idea she would write works featuring him for decades to come. A brief passage in "The Big Four" provides original information about Poirot's birth or at least