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,
The Adventure of Sherlock Holmes' Smarter Brother accompanied by a disguised Sherlock and Watson. Wilder was having lunch with producer Roth when it was suggested that Wilder spoof Sherlock Holmes. Roth approached Wilder again a week later and inquired if Wilder had given any more thought to the idea of a Sherlock Holmes film. Wilder replied "No, but I have given a great deal of thought to Sherlock's insanely jealous brother Sigi." In his autobiography, Wilder explained that he was further motivated by the experience of working with his "Young Frankenstein" co-stars Madeline Kahn and Marty Feldman and he wanted to write parts for both of them