Continuity mistake: In the opening scene when John is going to the refrigerator, a white skull can be seen on the left side of the kitchen table amongst all Sherlock's science equipment. When he closes the refrigerator door again after discovering the severed head, the skull has disappeared. As he's leaving the kitchen, the skull reappears. (00:03:25)Chitarra10
Character mistake: In the opening scene, Sherlock makes a point to correct Barry's poor grammar. But later, when talking to Watson, Sherlock uses poor grammar by saying "who's sleeping with who." It should be "who's sleeping with whom." Not a mistake Sherlock would make.Bishop73
Character mistake: Lestrade mentions that there could be some "poor sod covered with semtex on the streets somewhere" when talking about Moriarty's victims, but semtex does not go off via gunshot, much like C4. But that is what happens when one of the victims dies however, so the explosives are not semtex.
Continuity mistake: When Sherlock goes to look out the window at John leaving (after the tiff about the head in the fridge), his dressing gown is hanging off his right shoulder, exposing his t-shirt. Next there is a wider shot of him from behind, and his dressing gown is on straight, covering both shoulders properly. Then there's another closeup and it's off the right shoulder again. (00:05:40 - 00:06:10)Aerinah