Hercule Poirot is [Agatha Christie's]? primary detective, appearing in over 40 books. He was born in Belgium and has worked as a Belgian police officer, but moved to England after the war and started a second carrier as a private detective.
He meets what turns out to be a life-long partner, [Arthur Hastings]?, almost immediately after arriving to England. The books take us through the whole of his England living, from the first book ([The Mysterious Affair at Styles]?), where he is a refugee staying at Styles, to the last Poirot book (/Curtain?), where he stays at Styles once again.
Christie books with Hercule Poirot:
Movies Poirot have been appearing at movies, too, played by Peter Ustinov (Murder at the Orient Express).