Mycroft, the smart one, is watching a cheesy, almost porno-level of dialog, movie that looks like a black and white classic but is apparently an invention, a… pastiche. He knows this movie so well he mouths the dialog along with it, with apparent glee.
He is interrupted by John and Sherlock’s clown prank. “That was insane, why would he do that?” Mycroft says. Indeed, homeless network, rental costume, sure, but some of the elements… how did they make the paintings weep blood? WHY did they go that far?
To get to the truth, we – I mean, Mycroft had to be scared that bad.
(Seriously though, why would bbc let one of their flagship dramas have a finale w/o hyping it, even if it was bad… would they be so *disappointing*? And wouldn’t a Piccadilly circus thing in advance of a 4th ep BE that kind of hype? I’M NOT SAYING, I’M JUST SAYING)