Wow.... wow. Before I get too carried away, the drill is the same: this review will contain spoilers for the season 4 finale of Sherlock.
Jeez. I didn't realize that Sherlock's secret sister could be so psychotic, so evil, so scary. Let's start from the beginning again.
Mycroft is watching a tape in this old building when the video he's watching says ominously, "I'm back." Mycroft gets up and walks around the building, seeing shadows of someone. He had his umbrella with him and, to my surprise, pulled that umbrella apart to reveal a sword. It's funny how something that sounds so simple actually appears so awesome, so badass, when you see it on the screen. He walks forward and asks the person he knows is in the shadows to come out. Unbeknownst to the elder Holmes brother, Sherlock set the trick up only to berate Mycroft about not telling him about Eurus. Speaking of which, the last episode left us on a cliffhanger with her shooting John. Well, it turns out, he's okay, because it was a tranquilizer dart. I will admit that I wish they had at least told us where he was shot before he recovered.
Anyway, moving on!
Mycroft, John, and Sherlock go back to Baker Street and Sherlock asks Mycroft about Eurus and why he can't remember her. Well, it turns out she was psychopathic from a very young age and Sherlock's mind buried his memories of her and altered them to protect him. Remember Sherlock's dog, Redbeard? It turns out it's not a dog; Sherlock never had a dog! It turns out Sherlock imagined Redbeard to cope with the dark truth: Redbeard was really called Nemo Holmes, the third brother. And Eurus killed him!
I will say that this particular twist cemented everything for me: Sherlock being a man of logic rather than emotion, Mycroft keeping up the story of the dog to protect Sherlock, and Eurus being the most dangerous genius Sherlock ever faced.
While they are discussing Eurus and what to do, an explosive drone flies into the room and the three just make it out as the drone explodes. I'm honestly glad that that's what the explosion from the trailer was - at least they made it!
They then travel to Sherrinford to find out how Eurus escaped. I love what Sherrinford turned out to be. I love how Gatiss and Moffatt had everyone assuming Sherrinford was the brother and not a place. Smart move.
Once they get there, things get ramped up to an eleven. Eurus is in control of the entire ward. At this point, I was so afraid of her that I didn't even know what to think. We then go back five years where we meet Jim Moriarty once again, who visits Eurus without supervision by the staff. The sudden appearance of Moriarty scared the living crap out of me.... then I found out it was a flashback. Moffatt and Gatiss are way too good at scaring viewers.
We then watch as Eurus and Moriarty formulate a plan to end Sherlock.... at this point, I was absolutely terrified. Darker and edgier, indeed! Eurus, back in the modern day, forces Sherlock to play a dangerous game where he must shoot one of the ward's employees, tell Molly Hooper he loves her, and kill either John or Mycroft in order to move on. The game was the most terrifying thing to sit through, and if Sherlock didn't do as told she would blow up a plane with an innocent little girl inside. I was convinced at this point: Eurus is the most dangerous villain Sherlock has faced to date. Sian Brooke was brilliant playing her.
Sherlock refuses to shoot his brother and friend, so Eurus knocks him out and puts him in a holding cell, Mycroft in another room, and John in a well somewhere on site. She then forces her brother to solve the case of the Musgrave ritual.... Sherlock finds out that the little girl on the plane and Eurus are the same person. A child warped by fear of the world with no one there to help her since she got locked up. Sherlock finding her and comforting her was a perfect way to end the game, even if it was a little cheesy. But I like the idea of Eurus and Sherlock just being human in the end. She helps Sherlock to find the well (in which John is drowning at this point) and they rescue him just in time.
Eurus gets locked up again for all she did, but this time Sherlock is allowed to visit her. I found that to be perfect, because it fulfills both characters and they are both better people in the end. The episode ends with Sherlock and John back at the Baker Street flat, which has begun to be repaired from the blast and a video clip of Mary signing season 4 off.
Overall, even if it did get a little cheesy in spots, I feel like we needed to see that from Sherlock, not just the cold, calculating machine. Brooke was fantastic in her role and Martin Freeman delivered yet another amazing performance as John Watson. Mark Gatiss was on point as the foil to Sherlock. I'm glad we didn't see him exhibit any emotion, though, because it wouldn't have shown how Sherlock, though the younger, is the one who has grown. I hope Moffatt and Gatiss continue with Sherlock's story sometime in the future, because I feel there is a lot more that could be said. I hope to see Sherlock again soon.