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 childhood in or near the town of Spa, Belgium: "But we did not go into Spa itself. We left the main road and wound into the leafy fastnesses of the hills, till we reached a little hamlet and an isolated white villa high on the hillside." Christie strongly implies that this "quiet retreat in the Ardennes" near Spa is the location of the Poirot family home. An alternative tradition holds that Poirot was born in the village of Ellezelles (province of Hainaut, Belgium). A few memorials dedicated to Hercule Poirot can be seen in the centre of this village. There