The Adventures of Sherlock Holmes and Dr. Watson (film) invited to The Diogenes Club by Sherlock's older brother Mycroft. The club hosts the most unsociable men of London, and they have banned talking. Once there, Mycroft, asks him to help Lady Eva Blackwell. She is being blackmailed by one of the most villainous men of London, Charles Augustus Milverton who is demanding £7,000 for some letters he has stolen from her, threatening to release them to the public if she does not pay the ransom. Upon their release, the letters would cause a scandal that would end Lady Eva's marriage engagement. Sherlock agrees to help her. The same day,
Diogenes Club 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