Sherlock: “The Lying Detective” — 9 Spoilery Questions

Warning: This article contains MAJOR spoilers for Sherlock’s “The Lying Detective”…

Sherlockjust dropped a major twist at the end of “The Lying Detective,” revealing that Sherlock and Mycroft have a sister named Eurus. With only one episode left in Sherlockseason 4, here are all of the questions we need answered before this detective drama goes on another one of its seemingly interminable hiatuses…

Is Eurus Sherrinford or is there a fourth Holmes?

Um, this is the big one for us. We now know that Eurus is Sherlock and Mycroft’s sister, but then who is Sherrinford? Is that Eurus’ other name? Is Sherrinford someone else? Could Sherrinford be the facility where Eurus was being kept? Or does it refer to a fourth Holmes sibling? After all, there are three other winds besides the eastern one. And, as Sherlock laments in “The Lying Detective,” why do people always stop counting at three?

Sherlockwas not very clear on who or what “Sherrinford” exactly is (but we got another post-it note with the name written down on Mycroft’s desk). Hopefully, the shows clears that up next week. 

Where has Eurus been?

John jokes that Sherlock and Mycroft’s secret sibling is locked away in some tower, but Mycroft doesn’t laugh and, given what we know about what Eurus is capable of and her willingness to apparently shoot John Watson in the face, is it so crazy that Eurus might have been locked away somewhere?

When Mycroft first tips John off that he has another sibling, it is in the context of his siblings being threats and Mycroft’s role as their brother not necessarily meaning he can save them. Has Mycroft had to try to save Eurus before? Related question: Has Mycroft had to save other people from Eurus before?

What does Eurus want?

It’s clear that Eurus is targeting Sherlock in some way. She brought Moriarty back to “life” to get his attention. Furthermore, she starting text-flirting with his best friend, visited him as a client (pretending to be Faith Culverton), and posed as John’s German therapist. Obviously, Eurus is trying to get Sherlock’s attention — or so it would seem.

If this is the case, why didn’t Eurus just announce herself to Sherlock when she was pretending to be Faith? Why go undercover as John’s text girlfriend and then therapist for weeks only to (maybe) shoot him? This is a lot of work just to say hello.

Did Eurus know Moriarty?

Did Eurus use Moriarty’s viral video and “Miss me?” tagline because she knew the consulting criminal or just because she knew it would get Sherlock’s attention? When Eurus is explaining her relationship to Culverton Smith, she mentions that a “mutal friend” put them in touch. Sounds like Moriarty’s M.O., no?

Does Sherlock know Eurus?

It’s unclear how well Sherlock knows Eurus, especially as an adult. After all, he didn’t recognize her when she was in disguise as Faith or John’s therapist. Furthermore, it doesn’t seem like Eurus knows Sherlock very well, either.

When they go out to get chips as Sherlock and “Faith,” Eurus notes that Sherlock is nicer than she thought he would be — nicer than anyone. Has it been awhile since these two saw each other?

Is Sherlock Eurus’ twin?

In “The Abominable Bride,” Sherlock said “It’s never twins,” and Sherlockfandom has been waiting for when it is twins ever since. Could Eurus and Sherlock be twins? It seems worth noting that “The Abominable Bride” was written and released after Steven Moffat and Mark Gatiss decided on the Eurus twist. Moffat told RadioTimes:

The scene where Eurus finally unveils herself, we’ve been sitting on that since we sat talking about it on the production bus… when we were shooting “His Last Vow.” We’ve been talking about it ever since then.

Conversely, a fourth Holmes sibling, Sherrinford, could be Sherlock’s twin. If something happened to Sherrinford when the Holmeses were younger, it could have been the thing that pushed Eurus over the deep end.

Who was watching Rosie all episode?

At one point, John, Molly, and Mrs. Hudson are all in a scene together, begging the question: Who’s looking after Rosie? My head canon is that Lestrade is part of Rosie’s babysitters club and was looking after her in the aforementioned scene and I am holding onto that theory until proven otherwise.

Where is John’s sister Harri?

All this talk of siblings has us wondering about John’s sister…

In season one, we learned that John has an alcoholic sister named Harri. In season three, she didn’t show up for his wedding to Mary, implying that their relationship is, um, not good. Still, it’s pretty bad that Harri isn’t around in the time following the murder of John’s wife. Maybe the show just forgot about John’s sister? Or maybe she’s the one watching Rosie when every other character is accounted for and Rosie-less?

Has TD-12 already been used?

The TD-12 chemical Culverton Smith pumped through the veins of his friends and family to make them forget was a big plot point to drop in to only one episode and barely use. Might it come back into play for the final episode of the season. Is everything we have seen so far exactly what happened or has one or more of the characters been exposed to the memory-wiping drug?

For more Sherlock season 4 information, including the promo for next week’s season 4 finale, check out our Sherlock season 4 news hub.