Diogenes Club series "Sherlock". The Diogenes Club has appeared, in various forms, in a great many other settings, most of which take as given the Club's connection to the British Secret Service: Diogenes Club The Diogenes Club is a fictional gentleman's club created by Sir Arthur Conan Doyle and featured in several Sherlock Holmes stories, such as "The Greek Interpreter". It seems to have been named after Diogenes the Cynic (although this is never explained in the original stories) and was co-founded by Sherlock's indolent elder brother, Mycroft Holmes. The club is described by Sherlock Holmes in the story "The Adventure of
Mycroft Holmes [...] the most indispensable man in the country." He apparently serves as a sort of human computer, as stated in "The Bruce-Partington Plans": Mycroft appears or is mentioned in four stories by Doyle: "The Greek Interpreter", "The Final Problem", "The Empty House" and "The Bruce-Partington Plans". While he does occasionally exert himself in these stories on behalf of his brother, he on the whole remains a sedentary problem-solver, providing solutions based on seemingly no evidence and trusting Sherlock to handle any of the practical details. In fact, Mycroft's own lack of practicality is a severe handicap despite his inductive talents: