In "The Big Four", Agatha Christie gave him a mysterious "twin brother" named Achille
The book also features Achille Poirot, Hercule's twin brother (later revealed to be
... [DOC] [TLE] Poirot's Allies - Hercule Poirot [PAR] Hercule Poirot, the Belgian private detective from Agatha Christie's creative mind, 
... Hastings married a sweet young woman named Dulcie Duveen and they both 
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