Thoughts of a spoiler-y nature (both BBC and book) below the cut.
Overall, I have to say I was pretty satisfied with the finale.
The interaction between Sherlock and John was so much better this week than last. John seemed ornery and put-out with Sherlock throughout the whole show last week – even when Sherlock showed up at the last minute to help them – and it was kind of disappointing. And although I thought Sarah was a good character, and wouldn't mind seeing her around more, I thought she might have been introduced just a bit too early. I would have liked to see a little more development of John and Sherlock's relationship before introducing a rival for John's
This week had a little more focus on the interaction between the two men, so I was happy. The journalist/photographer bit was priceless and showed how in-synch they are, and how well they work together. I really liked that John kept trying to remind Sherlock that real lives were at stake, and I loved how Sherlock seemed genuinely concerned about John and his approval. During the "I've disappointed you, haven't I?" conversation, he looked almost ashamed for a moment before he caught himself and launched into his not a hero speech. I like the idea that John can pull more human emotion out of Sherlock than anyone else can.
I loved how they worked in the canon references throughout the show, and squeed every time I caught one. Sherlock being so put out over John’s description of him on his blog, and the back-and-forth over the solar system was adorable. And the “I’m lost without my blogger,” line had me rolling my eyes and giggling. It was a cute update and a nice tip of the hat to the original books.
The actor who played Moriarty was fantastic. He was creepy as hell, but almost charming in a way. And I thought his interaction with Sherlock was amazing. However, as much as I liked the actor and thought he pulled off evil genius well, I had a bit of a hard time believing that he was the evil genius. I've always imagined Moriarty as Holmes' age or older. (ever since rumors have started about casting for the new SH movie, Daniel Day-Lewis has been my Moriarty ;) He doesn't have to be ancient, just more… established? To me, this Moriarty seemed younger than Sherlock, and it kind of threw me. I had a bit of a hard time imagining that this young man could have amassed as much power as Moriarty is supposed to have in so short of time. But other than that minor issue, I really did like him and hope we'll get more of him next season.
As for the finale itself... overall, I was pleased with it. I thought having the final meeting at a pool was clever update to Reichenbach, and the tension in the final showdown was palpable. John and Sherlock's interaction was touching and the sparring between the two geniuses was perfect.
I was a bit surprised at the cliffhanger ending though. Not necessarily that there was one, but the type of cliff-hanger. When Sherlock walked into the pool, I was fully expecting to see FINA played out, and to see Sherlock 'die.' When Sherlock took aim at John's bomb-laced jacket, I was sure I knew what was going to happen next: He was going to shoot it, detonating the jacket and collapsing the building around him and Moriarty. Somehow, John would get out and then freak out trying to find Sherlock. Eventually, Sherlock would be declared dead, and the show would end with John typing in his blog about "the best and wisest man I have ever known." It would have been angsty as hell and so perfect.
What I didn't expect was the screen to cut to black without any sort of resolution. I'm not saying that I needed it to end my way, but the will he/won't he ending of what was supposed to be a three episode mini-series just fell a little flat with me. What if something happens and there isn't a second season? For such a strong show, I think it could have been given a better (and more explosive ;) ending.
Although, the ending has definitely convinced me that this was never intended to only be a three episode mini-series. A cliff hanger like that makes sense for a longer running show, but not for a one-shot. If this was truly intended to be only three episodes long, there would have been some sort of resolution at the end. I firmly believe that the creators wanted to do more with this, but the network would only order three episodes. So, knowing the fans would scream and demand more if they ended it with such a huge cliffhanger, they left the finale unresolved. I have to hand it to Moffat. The man knows his fanbase. :)
One thing that I absolutely hated this episode was Sherlock’s treatment of Molly. Sherlock Holmes may be cold and focused when dealing with a case, and he may be blunt and tactless when interrogating a witness. But Holmes was always a gentleman, and I don’t remember him ever being overtly cruel. Or, at least not cruel without some sort of case-related purpose. Even in CHAS, when he got engaged to one of Milverton’s servants to gain access to his house, he was able to (somewhat) justify it as for the good of a case, and by the fact that the woman had a second suitor waiting in the wings. But Molly wasn't a case. She's a colleague. One that's kind to him. And the way he tossed out “gay” when Jim came in, and then proceeded to smugly list in detail why her ‘boyfriend’ was gay was just cruel and unnecessary. And the weight comments? Seriously made me grind my teeth. There was no point to his behavior towards Molly other than to show just how much of a ‘sociopath’ he is. And that really didn’t sit well with me.
And if I can be honest? I loved the 'high-functioning sociopath' comment in the first episode. I thought it was hysterical and wonderfully delivered. But, I thought was just a snarky, toss-away line he used to shut Anderson up. I really tried not to read anything else into it. But it kind of looks like they might actually be leaning that way with him. Maybe not Dexter-level sociopathy, but still… I’m not so sure I like it. As fun as it is to read the occasional fanfic about sociopath!Holmes, I don't want to see that become canon. Even in this 'verse.
But all that aside, I really did love the show. Benedict Cumberbatch is a perfect Holmes and although I’m still sore about the missing moustache, Martin Freeman is a great Watson. Overall, I think the series is amazing, and I love how well they’ve modernized the classic. I can’t wait to see where they go with it next season. :)