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 matter of twenty years. None of the explanations is especially attractive. In terms of a rudimentary chronology, Poirot speaks of retiring to grow marrows in Chapter 18 of "The Big Four" (1927) which places that novel out of published order before "Roger Ackroyd". He declines to solve a case for the Home Secretary because he is retired in Chapter One of "Peril at End House" (1932). He is certainly retired at the time of "Three Act Tragedy" (1935) but he does not enjoy his retirement and repeatedly takes cases thereafter when his curiosity is engaged. He continues to employ his