Continuity mistake: Early in the episode Sherlock and Dr. Watson enter a cab in daylight for a ride to the crime scene in Brixton, which is a part of greater London. It is night when they arrive.
bnemirow
22nd Jan 2015
Sherlock (2010)
22nd Jan 2015
Sherlock (2010)
Other mistake: At the end of the episode, the evil Shan is texting with (most likely) Moriarity. She is sitting at a desk facing a wall and yet the laser targeting ray appears directly on her forehead, which could only come through a window directly opposite her.