In Agatha Christie's short story, "The Chocolate Box," Poirot describes a case he was unable to solve. Investigating the apparent poisoning of a popular Belgian civil servant, Poirot goes undercover to expose the murderer, only to discover the case is not so tidy as he thinks. But who could have wanted the man dead? This short story originally appeared in the May 23, 1923 issue of The Sketch magazine.