Sherlock: 'The Final Problem' Explained

The Cast of Sherlock Season 4

[This post contains SPOILERS for Sherlock: The Final Problem.]


Last night saw the finale of Sherlock season 4, and what a finale it was, with showrunners Steven Moffat and Mark Gatiss delivering an episode that was confusing for viewers and left lots of questions unanswered. However, for all the action, Sherlock also told a story with real heart; something we’ve not necessarily seen from the show before. In fact, this whole season has given viewers a much closer look at Sherlock’s innermost thoughts, and the way in which he interacts with those around him.

Look past the muddled, on-screen action, and there was subtle, emotive insight given into the man who considers himself to be a sociopath. Sadly, that got a little lost, but when we break down the episode, there were some great moments during which we got to learn a whole lot more about Sherlock’s characters.



For all the speculation over who Sherrinford was, it turns out it was the name of the place where Eurus was being held. Such secure institutes do indeed exist, though it seems realistic to expect (or hope) that they might be harder to infiltrate than Sherrinford was. Still, anything to see Mark Gatiss dressed as a fisherman works for us. Weirdly, or perhaps in keeping with the rest of the episode, Eurus seemed to be remarkably well adapted for someone who had been incarcerated in more or less solitary confinement since childhood. Certainly, she knows enough of the world to be able to play a convincing therapist, ingénue, and daughter of a psychopath.

The biggest trouble with Sherrinford is that the concept itself was rife with implausibilities. Surely Sherlock would have noticed there was no glass? Surely setting up room after room of Moriarty video messages and strange little games would have taken a great deal of preparation? Or is Eurus just brilliant at absolutely everything? The one purpose the institute did serve well, was that of a red herring; by using the name associated with the third Holmes sibling, Gatiss and Moffat ensured that many were taken in by the “Call Sherrinford” references dropped in throughout season 4.


Sherlock - The Great Game

Still dead, sadly. Given the way 'The Final Problem' played out, it would have been more believable to see Moriarty come back from the dead than it was to believe he had taken the time to record several video messages for Eurus to use sometime in the future. “And Holmes kills Holmes,” he mused on screen, followed by endless “Tick-tock’s” that make you wonder what the world’s evilest mastermind really did with his time. Still, it was interesting to see that Eurus had requested a meeting with him as one of her "gifts" from Mycroft.

Clearly, Eurus used Moriarty to get to know Sherlock’s weaknesses, with John being one of them, which is presumably why she had posed as the mysterious E and started a text affair with him. In turn, Eurus had obviously been sharing family secrets with Moriarty, better allowing him to get inside of Sherlock’s head. According to Eurus, she is Moriarty’s revenge, so in essence, her games are all part of his posthumous plan. As it happens, Moriarty obviously knew Sherlock far better than Eurus does; he worked out that Holmes will indeed kill Holmes, because he knew Sherlock, when faced with choosing between John or Mycroft, would rather shoot himself. Eurus didn’t though, and that’s when she became panicked.

Eurus Holmes:

After the big reveal at the end of 'The Lying Detective,' we already knew that Eurus Holmes was not of sound mind. As many had suspected, Eurus’ intellectual capabilities far outweigh Sherlock and Mycroft’s, and she is clearly lacking any ability to feel emotion. Aged just five, she had to ask big brother Mycroft what pain was. Despite that, though, we did get glimpses (thanks to Siân Brooke’s brilliant portrayal) of emotion where Sherlock was concerned, though the writing made it difficult to ascertain whether this was because things weren’t going according to her plan -- such as when Sherlock turned the gun on himself -- or whether it came out of genuine concern.

By the end of the episode, though, Eurus refused to speak to anyone, she would play violin duets with her brother, which hints at there being some kind of bond between the pair. It should also be noted, though, that she seemed entirely okay with the potential demise of her eldest brother, Mycroft; even asking Sherlock to kill either him or John, the latter of whom she never mentions in regard to their illicit dalliance.

In fact, Eurus Holmes kills without thought or concern; the therapist she impersonated, the three brothers hanging in front of the window (a clever reference to Arthur Conan Doyle’s 'The Three Garridebs'), the prison governor (by default) and his wife, all ran afoul of Eurus’ penchant for ending other people’s lives, and yet she can seemingly integrate into society as needed. Eurus is also very good at using emotion to get others to do her bidding. In addition to playing on Sherlock’s conscience with the fake plane crash scenario, she also had all the guards at Sherrinford under her spell.

Even if we ignore the fact that this borders on some kind of superpower more befitting of a Marvel show, Eurus’ abilities raise the question of what happens in the future. Surely, even with new staff in place at Sherrinford, Eurus could then use them to do her bidding, too? What about Sherlock, or Mr. and Mrs. Holmes? If Sherlock does return, it will be interesting to see if Eurus is mentioned or seen again, though this being Sherlock, it seems very doubtful indeed.


Trevor Redbeard Sherlock The Final Problem

Not a dog, it seems, but a boy. Victor, in fact, who was Sherlock’s childhood friend. The pair would play pirates together for hours on end, while the older Mycroft brooded about, and the younger Eurus would watch with jealousy burning inside of her. In fact, Eurus felt so angered by Victor and Sherlock’s closeness, that she threw Victor down a well, where he drowned, because Sherlock couldn’t solve her rhyme which detailed where he was.

The implications of Eurus’ actions are mind-boggling. It would have been nice to hear mention -- even in passing -- of Victor’s parent’s reaction, but alas, the episode was too full already. As it was, though, it became clear that this -- along with a bit of arson -- was the reason Eurus was locked away; for her safety and others. In his terror, Sherlock had changed his memory of Victor into a dog named Redbeard; and it is this that’s been haunting his dreams for a long time. He had also erased all memories of having a sister, and who can really blame him?


Mark Gatiss and Benedict Cumberbatch in Sherlock Season 4

Arguably, this episode belonged to Mycroft, since we finally got the insight into the eldest Holmes sibling that we’ve been missing since season 1. For that, 'The Final Problem' must be praised, as must Gatiss, who really excelled. We learned that Mycroft has a penchant for melodramas, that his umbrella really does double up as a sword (knew it!), and that he’s rather terrified of clowns. In one of the best moments of the whole Sherlock series, we also learned that Mycroft played Lady Bracknell in a production of The Importance of Being Earnest and Sherlock thought he was rather good. Amusing as it was, those few lines of dialogue between the brothers really showed how important Sherlock’s approval is to Mycroft, and by the end of 'The Final Problem,' it was evident just how much he cares for his family.

When Sherlock was faced with the choice of killing his brother or John, Mycroft was quick to try and provoke Sherlock into killing him, because he knew it would destroy his brother to kill his closest friend. He also tried, multiple times throughout his life, to protect both Sherlock and their parents. Okay, so telling them that Eurus had died might not be the best thing to do, but Mycroft genuinely thought he was doing it for the best. Also, the trigger words he kept throwing at Sherlock over the years served as a way of checking on his little brother’s mental health, without forcing Sherlock to confront the past he had buried. While much has been made of and discussed concerning Mycroft’s role in the government, the horror he clearly felt at the thought of killing the governor said all it needed to; Mycroft might be cold, and aloof, but he has a heart.


Martin Freeman as John Watson in Sherlock The Final Problem

Another strong performance from Martin Freeman, who has played a blinder all season. John’s (platonic) love for Sherlock became clear, as did his devotion; this man was willing to orphan his child in order to be by his best friend’s side. Both men are damaged, haunted by past memories that have shaped them (John "never came home" from the war and has recently lost his wife) and, to be blunt, they need each other. John knows this, and has known it for far longer than Sherlock has, but he allowed his friend to get to the realization on his own. By doing that, John strengthened the friendship between the two, which seemed to become reinforced in the wake of Mary’s death.

In Sherlock, a lot of the emphasis has been on Sherlock needing John, but last night it also became clear just how much John needs Sherlock in return, and how much his few affectionate comments mean to him; in particular, the exchange between Mycroft and Sherlock when Mycroft said John had to leave because they were discussing family matters. “That’s why he stays!” Sherlock yells, and John settles back in the chair with a small, contented smile playing on his face. The biggest disappointment came in the fact that John has seemingly gotten over Mary’s death with comparative ease. Granted, we are not aware of how much time has elapsed since 'The Lying Detective,' but it seemed odd that we didn’t see or hear much concerning her death other than a fleeting reference. Surely he must’ve experienced some guilt when confronted with Eurus again?


Benedict Cumberbatch as Sherlock in The Final Problem

Turns out, he is human after all. Except we all knew that, of course. Arguably, both 'The Six Thatchers' and 'The Lying Detective' showcased more of Sherlock’s emotions than 'The Final Problem,' but nevertheless, Sherlock, in a series of tests set by his sister, showed us what he was made of. Louise Brealey gave a heart-breaking performance as Molly in the few short minutes she was given, as the recipient of a call from Sherlock. When Eurus convinced Sherlock that Molly would die unless he could get her to say “I love you,” the fanciful, far-fetched game remained so, but also took on a new level of depth, as we saw how painful it was for Molly to be put through the mill by Sherlock, again. Worse still, Sherlock could see all this unfold, and if watching her ignore his call was upsetting, then watching the way she reacted when Sherlock uttered the three words to her was downright brutal. However, seeing Molly reappear at the end as if nothing was, or ever had been, amiss, kind of destroyed the painful beauty of that moment.

Then we had the ultimate decider, when Sherlock had to choose to kill John or Mycroft. The scene itself was left lacking, unfortunately, but what was really at play here was the relationships that Sherlock has with the two most important people in his life. He loves them both, that much is clear, but perhaps the fierce need he felt to protect them both spoke to him, too. Here is one relationship that is a lifelong bond. Blood makes Sherlock and Mycroft brothers, and chance makes John and Sherlock best friends, but its love that made Sherlock turn that gun on himself.

What of Eurus, though? Sherlock’s final problem was how to help his sister. The answer came in the form of attention, it seemed. Eurus had been missing that from her brothers and sadly, this was the only real explanation we were given to her behavior. We learned that Sherlock had no memory of his sister, because he had deliberately blocked it out. While we might have assumed that Sherlock’s realization would give Eurus context, it actually turned out to be the other way around. The way he spoke to the little girl on the plane, the way he wouldn’t choose between John and Mycroft, and the tender way in which he coaxed Eurus into his arms actually showed empathy; a thing which many thought Sherlock was incapable. Both Mycroft and Eurus’ failings expose Sherlock as the smartest one, despite Mycroft’s multiple digs to the contrary, because he knows the importance of love and friendship, and he knows how to treasure those relationships. For now, at least.


Screen Rant will have more information for you on the future of Sherlock as details are made available.

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