The Diogenes Club

The Diogenes Club is a fictional gentleman's club created by Sir Arthur Conan Doyle and featured in several Sherlock Holmes stories, most notably "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 stories thus:

Although there is no hint in the original Sherlock Holmes canon that the Diogenes Club is anything but what it seems to be, several later writers developed and used the idea that the club was founded as a front for the British secret service. This may have its root in "The Adventure of the Bruce-Partington Plans", in which Mycroft Holmes is revealed to be the supreme and indispensable brain-trust behind the British government, who pieces together collective government secrets and offers advice on the best way to act.

The idea was popularised by The Private Life of Sherlock Holmes (1970), a 1970s motion picture directed by Billy Wilder, and has since been frequently used in pastiches of Conan Doyle's stories as well as the TV show 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:

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