After Shylock left, moriarty's video was broadcast on national television signals. It turned out that moriarty was not killed in the initial falling case, and everything was foggy. In order to reveal the truth that moriarty is not dead, Shylock is once again called back to London by Mycroft to solve the case.

Adapted from arthur conan doyle's detective novel The Adventures of Sherlock Holmes, the play moves the original time background from19th century to 2 1 century, and tells the story of a series of dangerous and unusual adventures experienced by fashion detective Sherlock Holmes and his friend John H. Watson in the bustling London metropolis.

After watching the movie Atonement, steven moffat and sue vertue expressed their appreciation for benedict cumberbatch and hoped that he could play Sherlock, so Benedict became the only candidate for the role of Sherlock.

Finding Watson's actors is more difficult than finding Sherlock. Several actors auditioned for the role of Watson, and finally Martin Freeman got the role. The screenwriter pointed out that Martin helped Benedict shape the way to play Sherlock.