If you thought 'Sherlock' was done with the big plot twists after that shock death in episode one, you, and the rest of the world, were terribly, terribly mistaken. That much was clear at the end of last night's instalment 'The Lying Detective', when a brand new character was introduced to the drama.
Sherlock has a secret sister and she's been hiding in plain sight since the beginning of season four.
We'd been tricked. Sherlock's secret sibling wasn't a brother called Sherrinford played by Tom Hiddleston. He's got a sister, called Euros (Eurus?) who has been in disguise this whole time as the woman John was texting, the fake daughter of Culverton Smith AND John's new therapist.
Even during the reveal there was some confusion about how tricked we'd been
In fact, some of us are wondering if the trick could still be going on...
We're still not 100 per cent sure what is going on or how we feel about it.
So why did it come as such a shock?
It's fair to say we were distracted by creepy new villain Culverton Smith, who was downright terrifying and immediately sparked serious discussion on social media:
And the emotional depths of the episode, which saw Sherlock and John deal with the death of Mary:
And, let's not forget, her disguises were so good that even Sherlock didn't deduce what was going on.
What this secret sibling plot twist means for the future of Sherlock, we don't know. What's her story? Where has she been? Why is she back? And did she really just shoot John Watson?
This is the only thing we are sure of.
Did you see that plot twist coming? Let us know in the comments box below.
'Sherlock: The Final Problem' is in cinemas and on BBC1 on Sunday at 9pm.