SEASON FINALE: When Sir Arthur Conan Doyle wrote the Sherlock Holmes story The Final Problem in 1893, it was to do away with the character of his popular detective, whom the author felt was, by that time, a burden. So at the end of the story, Holmes and his evil nemesis, Professor Moriarty, were sent over Reichenbach Falls in a locked, battling embrace to the death. Popular demand forced the resurrection of the character – and since we know the TV Sherlock series is continuing past tonight’s season finale, we know tonight's season ender, The Reichenbach Fall, is not as final an ending as it seems. But my, it’s a gripping one – transplanted to a London rooftop, with Andrew Scott’s Moriarty and Benedict Cumberbatch’s Holmes engaged in another high-altitude duel of wits. Check local listings.