What is the name of Agatha Christie's famous Belgian detective?

Agatha Christie’s famous Belgian detective is Hercule Poirot.

Poirot first appeared in Christie’s debut detective novel, The Mysterious Affair at Styles, published in 1920. A former Belgian police officer and refugee living in England after the First World War, he becomes a private investigator whose cases take him across Britain, Europe, and the Middle East.

Poirot is known for his fastidious clothing, carefully waxed moustache, precise habits, and reliance on what he calls his “little grey cells.” Rather than depending mainly on physical pursuit, he solves crimes through logic, psychology, interviews, and close attention to contradictions in witnesses’ stories.

Readers sometimes confuse Poirot with Miss Marple, another Christie creation. Miss Marple is an English village sleuth who relies heavily on observations of human nature, while Poirot is a Belgian former policeman with a more formal, analytical style. Poirot appeared in 33 novels, two plays, and 51 short stories, ending with Curtain in 1975.