Warning: Spoilers ahead. Do not read if you haven’t already watched The Lying Detective.
In an ending that was more Scooby-Doo than Arthur Conan Doyle, Sherlock finally answered the question that many fans have been asking over the last year – is there a third Holmes sibling?
Creators Mark Gatiss and Steven Moffat have teased the possible introduction of another Holmes brother on numerous occasions, jokingly posting pictures on social media with Tom Hiddleston and adding in nudges and winks about a mysterious ‘Sherrinford’.
Scholars of Doyle's original books have written about the possibility of an older sibling bearing that name, but as ever, Gatiss and Moffat couldn't resist throwing in an extra twist.
Holmes and Mycroft don't have a brother, they have a sister – Euros (Sian Brooke). Not only has she been leading her brothers up the garden path and controlling their moves, she's now holding a gun to John Watson's head and apparently pulled the trigger just as the closing credits rolled.
Rounding off an episode that included a drug-addled detective, a seriously creepy Jimmy Savile-esque villain and an emotional reunion for Holmes and Watson, viewers’ heads were left spinning.
Here are our 6 burning questions after The Lying Detective:
1. Who is Euros? What does she want?
Sherlock has alluded to an extra Holmes sibling in the past (Mycroft previously remarked “Remember what happened to the other one?”), but it was still a shock when Watson's seemingly innocuous therapist peeled back the wig and took out her contact lens to reveal herself as Sherlock’s sister, Euros.
Not only had Euros been playing Watson for a fool – she was the woman on the bus in The Six Thatchers – she's also pulled the wool over the eyes of Sherlock and Mycroft. No small feat.
So what is Euros game? What happened to her that has prompted her to seek revenge on her siblings? Where has she been for all these years? What is her end goal? And did she just pull the trigger on Watson?
2. Moriarty is definitely dead. Right?
At the end of The Last Vow, it was hinted that “an East wind is coming”. Many presumed that this was some allusion to the return of Moriarty or a new villain, but it was actually a play on words. Euros is named after the Greek god associated with the ‘East wind’.
The fact that Euros has been taunting Sherlock and Mycroft with the ‘Miss me?’ remarks suggests that Moriarty is definitely a goner and their sister has just used Andrew Scott’s character to play games with her brothers.
So Moriarty is definitely dead. Unless of course Moffat and Gatiss have more twists in store for next week’s finale and at this stage we wouldn’t put anything past them.
3. Will Toby Jones pick up some awards for Culverton Smith?
Villains very rarely pick up the gongs at awards season, but surely Toby Jones deserves a mention when the TV Baftas and Emmys roll around this year?
His fiendish and terrifying ‘entrepreneur’ was a celebrity who got away with his crimes in plain sight.
The references to Culverton’s political and royal connections, his work in children’s hospitals and pictures of his charity fun runs were direct references to Jimmy Savile and the BBC will almost inevitably face criticism from some quarters for alluding to the disgraced star.
4. Who or what is Sherrinford?
We're no closer to knowing who or what the mysterious Sherrinford is that Mycroft is so desperate to get speak with. It was previously believed that it may be the third Holmes sibling (maybe there’s a fourth?), but it’s seems more likely we should be asking ‘what is Sherrinford?’ rather than ‘who?’.
Our only guess at the moment is that Sherrinford is a person or building that Mycroft believed was containing Euros.
5. What is the significance of Sherlock Holmes’s old dog Redbeard?
There have been constant flashbacks to Sherlock’s old shaggy dog and it looks likely that the hound is somehow involved in Holmes and Mycroft’s relationship (or lack of it) with Euros. If Euros harmed old Redbeard, she immediately wins the title of the worst villain of all time.
6. Can Una Stubbs get her own spinoff series?
Car chases, men locked in her boot, saucy antics with handcuffs? There’s so much to Mrs Hudson that we didn't know. If Cumberbatch and Freeman are too busy to film any more episodes, Moffat and Gatiss should create a spinoff for their tea-making landlord in the meantime.
Do you have any theories about what will be revealed in next week's episode The Final Problem? Did you enjoy The Lying Detective? Let us know in the Comments below.