The opening sequence of the movie is inspired by Sir Arthur Conan Doyle's original Sherlock Holmes story "The Red-Headed League." In the story, Sherlock Holmes captures John Clay and his accomplice, Archie. John Clay even calls out at one point, "Jump, Archie, and I'll swing for it!"
Peter Cook, who plays Norman Greenhough, the Editor of the 'Strand' magazine (in which Watson's accounts of the Sherlock Holmes cases appear) himself played Sherlock Holmes in a 1978 version of "The Hound of the Baskervilles".