The Memoirs of Sherlock Holmes

The stories of 1892 and 1893, with cases from Holmes's past such as "Silver Blaze", where the racehorse vanishes and the dog doesn't bark, and "The Greek Interpreter", which introduces Mycroft, the detective's older brother. The book ends with "The Final Problem", in which Professor Moriarty, a mathematician and London's crime boss, steps in, and the chase takes Holmes and Dr. Watson to Switzerland. The story ends at the Reichenbach Falls, in an ending Doyle meant to be the last.

1. ChangeA one-story villain

   In the book, Moriarty appears in person only in "The Final Problem". The 2011 film makes him the villain of a whole feature.

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2. ChangeWatson away from the falls

   In the story, a false note about a dying Englishwoman draws Watson away from Holmes at the falls. In the film, Watson travels with Holmes for much of the trip.

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3. ChangeMycroft grows

   Mycroft first appears in "The Greek Interpreter", in this book, and briefly in "The Final Problem". In the film he is Stephen Fry, with bigger scenes.

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4. ChangeChess instead of a note

   In the story, Watson never sees the duel: he only finds Holmes's farewell note and the signs of a struggle by the falls. In the film, Holmes and Moriarty play chess on a balcony during a peace conference.

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