2x21 The Man with the Twisted Lip Sherlock Holmes & Mycroft Holmes
2x21 The Man with the Twisted Lip Sherlock Holmes & Joan Watson
2x21 The Man with the Twisted Lip Joan Watson
2x21 The Man with the Twisted Lip Holmes, Watson & Detective Bell
The arc of the Mycroft-centric finale actually starts in the May 1 episode.
"He has a cryptic conversation that seems to suggest he has some sort of agenda that involves Sherlock," executive producer Rob Doherty says. "We will be explaining that call and his relationship to the person on the other end of the line. … Mycroft is not all that he appears to be. Mycroft has a lot of explaining to do."
While the reveal will obviously land hard on Sherlock, Joan will also reconsider her professional goals as she wrestles with how her partnership with Sherlock has become her entire life.
2x21 The Man with the Twisted Lip Promo Is there a bug in here?