Hercule Poirot and Frank Howel Evans' Monsieur Poiret, a retired Belgian police officer living in London. A more obvious influence on the early Poirot stories is that of Arthur Conan Doyle. In "An Autobiography", Christie states, "I was still writing in the Sherlock Holmes tradition – eccentric detective, stooge assistant, with a Lestrade-type Scotland Yard detective, Inspector Japp". For his part, Conan Doyle acknowledged basing his detective stories on the model of Edgar Allan Poe's C. Auguste Dupin and his anonymous narrator, and basing his character Sherlock Holmes on Joseph Bell, who in his use of "ratiocination" prefigured Poirot's reliance on his
The Invisible Detective a darkened room. In fact, Brandon Lake does not exist; he was invented by the four children, who investigate all his cases themselves. Art plays the Invisible Detective in weekly sessions held in a darkened room, during which the Detective addresses the concerns of local residents, in exchange for a small fee. Each book also has a parallel subplot set in the 2000s, where Art's grandson, also named Art, and his friend Sarah have related mysteries to solve. The titles in the series are: The series revolves around the cases of eponymous detective, Brandon Lake. The books' protagonists are the