The 'Sherlock' Season 4 Finale 'Will Blow You Away'

The first two episodes of "Sherlock" Season 4 brought multiple shocks, and Sunday's finale is ready to blow fans away with more -- making you laugh, cry, and scream. The third episode, "The Final Problem," was written by show creators Steven Moffat and Mark Gatiss, and the vague synopsis just warns that "long-buried secrets catch up with Sherlock (Benedict Cumberbatch) and Watson (Martin Freeman)."

Some lucky fans and critics got an early look at the episode at a screening on Thursday. Here are a few reactions:

People laughed, people screamed and people definitely cried #Sherlock #tfp #thefinalproblem
— DoroDorothy???? (@Hingit83) January 12, 2017

OMG.
Moftiss took us to a very dark and distressing place. This episode will blow you away. very very very very thrilling! #Sherlock #BFI
— lichtblickpink (@lichtblickpink) January 12, 2017

Was very lucky to be at the screening of #sherlock The Final Problem. So many twists and surprises I can only say 'Eeek!' Extremely loudly
— Nick Cannon (@nickycafc) January 12, 2017

The Final Problem: all the stops most definitely pulled out. #Sherlock
— boydhilton (@boydhilton) January 12, 2017

Just out of seeing #Sherlock The Final Problem. What an episode. Best episode of series 4 by far.
— Cumberbatchweb (@cumberbatchweb) January 12, 2017

#Sherlock S4E3 The Final Problem: the tension is so through the roof we're trying to pick ourselves up off the ceiling. More tomorrow.
— Sherlockology (@Sherlockology) January 12, 2017

ICYMI: Here's our SPOILER-FREE REVIEW of #Sherlock S4E3 The Final Problem for your brain to consume: https://t.co/ryhCB4xprW pic.twitter.com/a00EOPKsle
— Sherlockology (@Sherlockology) January 13, 2017

Here's the Episode 3 promo:At the screening, Moffat said a fifth season is "possible," but he didn't confirm. He and Gatiss also shared more details on Episode 2's major revelation, and you can read details on that spoiler over here.