Finally caught up. The scene where Sherlock is shot and deduces his way out of a fatal injury is amazing, as are the scenes in the facade where John discovers Mary's secret, and the scene after at Baker Street. Freeman really carries the emotional weight of the show, being the most 'normal' person there for us to relate to.
A lot of people criticising how Sherlock is let into Appledore with a gun, and simply shoots Magnusson in the head. My justification is that Magnusson thought he had defeated Sherlock with the laptop. The police would find no physical vault, so Sherlock would be charged with trying to sell government secrets.
But he underestimated Sherlock's willingness to protect John and Mary. As he says during the wedding, he vows to do everything he can to keep them safe. CAM doesn't think this would go as far as murder, so why check them for weapons?
Yeah, it falls apart a little when you consider a) CAM had them checked for weapons earlier in the episode, and b) CAM threw John into the bonfire to test Sherlock's resolve and find his "pressure point."
Also, I don't understand how people think the show is getting more and more farfetched. I mean, the first episode has Sherlock determine a car's route from his memory of the London streets, and almost instantly create a route on foot to intercept it. Even the first episode introduced Sherlock's arch nemesis, giving the show a sort of comic book feel. They're basically superheroes whose powers are in their brains.
The more I think about it, basically CAM was pretty stupid too, eh? He was almost killed by Mary (how the hell did she get into his office by the way??), kneels and begs for his life like a coward, but he didn't learn a lesson from that and instead he didn't even bother to frisk Sherlock for a gun and blab out his mind palace secret for Sherlock to blow up. Tsk tsk.
Mary was cheating on John with Janine, and their relationship gave Mary access to CAM's office.
Fanfiction in progress.
EDIT: Doh. Just remembered than Janine was Mary's bridesmaid. I suppose she could have used that. Janine, worst PA 2014.