Hi, Sherlockians!
I watched Season 4 with hope in my heart and fingers crossed. While there were some things to like in every episode, my overall reaction was:
Season 4 Episode:
1. Not Sherlock
2. Yay, a new Sherlock episode!
3. Not Sherlock
I was disappointed, but at least this year I was prepared. Season 3 remains in my mind as the season that Sherlock jumped the shark. Unfortunately, Season 4 didn't recover, and (perhaps subconsciously) the authors brought in real-live sharks to warn us.
I appreciate the difficulty Moffat and Gatiss faced: it's deuced hard to write a genius. And in Sherlock you have two frequently onscreen, because they decided to make Mycroft a regular character (who only appears twice in all the stories). And they made Moriarty a recurring villain (vs one who appears once and is alluded to twice).
That's three geniuii you're balancing all the time. Most normal humans aren't up for the task of even _one_ genius, and for all their wonderful plot twists and banter, Moffat and Gatiss are in the end just a couple of ordinary humans who are trying their best to pay homage to this brilliant creation, and in the end could only find their way out of the puzzles they set by reducing the genius of the characters.
Alas. Same thing Orson Scott Card did in Ender's Game, to the detriment of that whole world. Ender's Game was the best thing Card wrote (and I've read a lot), and Speaker for the Dead, its follow-up, was nearly as great. Then, everything went downhill. The third book in that series was relatively poor, and the 4th barely readable. Then (and this parallels what Moftiss did), Card started a new series "Ender's Shadow" featuring minor character Bean from the first book, and proceeded to tear down his wildly successful character Ender by showing he wasn't a genius after all, Bean was, and everyone is playing Ender. Which is such a violation of the character, because Ender's overriding trait is his exceptional empathy, much as Sherlock's is his deduction. When you wrench the plot around so your main, beloved character is no longer exercising his overriding trait, your readers not feel merely disappointment, but betrayal.
Which is why I got off the Sherlock fan wagon back in Series 3. It's impossible-- I stand by this-- impossible for Sherlock not to have discovered Mary was a secret agent. Never mind whether you agree with this background for Mary or not, she simply couldn't have pulled it off. Sherlock is an exceptional observer and researcher; that's what he does. She'd have been deduced into the open within days. So the Mary plotline was unbelievable from the off. Again, Moftiss had minimal source material to work with, because in the stories, Mary's only a player in one of them, and basically blesses John to run off with Sherlock whenever the game's afoot.
So they invented this character who is better than John-- which Sherlock actually says to John in S4 episode 1, "She's better at this than you are," which completely invalidates John's character. Okay, bye! We've already invalidated Sherlock's character by having him continually hoodwinked by... oh, just about everybody. Now there's nobody left acting in their original capacity, and the gorgeous dynamic that Arthur Conan Doyle set up and has endured all these years just fritters away in the wind.
Moftiss and ACD both said that writing those brilliant bouts of deduction were the hardest part of the story. Well, that's the show. If you aren't going to write about deduction, you're not writing Sherlock. So S4 episodes 1 & 3 fail in that there is no plausible deduction or case going on at all. I just rewatched Seasons 1 & 2, and the contrast is stark. The reason Sherlock is no longer a hit is because it's not doing what it did to make it a hit. It became a soap opera.
S4e2 fares better in that there actually was a villain involved that Sherlock ensnared in a way relatively faithful to canon. But more, look at the motivation. Sherlock does what he does out of love for John. He wants to save John, his friend. That was his beautiful motivation in jumping off the roof at the end of Season 2. The tortured "explanations" (which are all balderdash) that Moftiss came up with in S3 to explain his survival all failed because they didn't proceed from that basis. Sherlock was tricking, being clever at John's expense-- was actually cruel. When you take love and turn it into cruelty, you've exploded the main theme of Sherlock and taken away your viewers' reason for watching.
Readers will hang with a deviation a little while, but you'd better have a good payoff in store for their patience. The way the series stands, we have 6 shows with the guys being friends and 6 shows where John hates Sherlock, or at least really doesn't want to be around him any more. It's like how the reboot movies always make Spock emotional. In the original series TOS, out of 79 episodes, Spock was emotional in maybe 3 of them. In the movies, he's emotional every time. The reason the emotion worked originally is because it was such a departure, it had shock value. It highlighted the struggle the character went through all the time, and had HUGE emotional payoff. It made us more sympathetic to the character all the time because we knew what he was suppressing. However, when those emotional outbursts become the norm, your Vulcan is reduced to a slightly odd-looking human. The whole character is diminished.
So, by making Sherlock _not_ the smartest guy in the room, you diminish him. The first time they did it, with Irene Adler in Season 2, there was all sorts of outcry because in the end, Sherlock had to save her, as opposed to her beating him in a game of wits. "Oh, but we had to!" Moftiss replied. "Because Sherlock is always the smartest guy in the room and the show is called Sherlock and get over yourselves already." Okay, fine. Then they proceeded to make him not the smartest man in the room with Moriarty (who actually calls him "doofus!" because who would believe in a magic code?). Never mind, we'll accept this too, because Moriarty was the arch villain in canon so he has to be Sherlock's match.
Then we get into Season 3 and Sherlock is smarter than nobody! He can't figure out Mary, he doesn't outwit Magnussen, but simply murders him because he failed (like, WTF?)-- he can't even outwit the photographer. This isn't Sherlock. I don't know what it is, but... actually I do. It's two normal guys who either didn't bother to put in the work or actually tried and to their chagrin discovered they couldn't be as brilliant as the character demanded they be. So they transmuted the show to soap opera or Bond or whatever you want to call it, changing the material into something they could write because the show they started writing got too hard for them.
I'm sorry for that. I'll always have and enjoy Seasons 1 & 2. Yes, they have faults, much as the first Lord of the Rings movie has faults, but I love it the best because it's closest to Tolkien's world. Sherlock S1 & S2 are closest to ACD, with the delightful updates Moftiss made to bring those stories into a new era and show that the detective, and his awesome biographer, certainly update well. I'm sure they would again, if the creators decided to return to the show they originally intended to pay homage to. I fear the reason they won't is... they can't.
Which makes ACD's achievement even more extraordinary. Thanks, bro. You did good.
Added: This is freaking brilliant!
http://blogs.spectator.co.uk/2017/01/sherlock-holmes-mystery-murdered-script/