(v3 Preview) In “The Final Problem,” one of the stories in The Memoirs of Sherlock Holmes by Sir Arthur Conan Doyle, Sherlock Holmes faces his greatest adversary, Professor James Moriarty—a criminal mastermind he calls the “Napoleon of crime.” Knowing Moriarty plans to destroy him, Holmes flees London with Dr. Watson, pursued across Europe. The chase ends at the Reichenbach Falls in Switzerland, where Holmes and Moriarty confront each other. Watson later finds signs of a struggle but no bodies—only Holmes’s note of farewell. Believed dead, Holmes sacrifices himself to rid the world of Moriarty’s evil, marking his apparent final adventure.