Here's everything we know so far about the new season of Sherlock...

Sherlock Season 4 Latest News
We have the first two episode titles for Sherlock season four. Much of the cast and behind-the-scenes team gathered in London this past weekend for Sherlocked UK, an extremely well-organized fan event, and revealed the episodes titles. The official Sherlock fan account later tweeted them out...
That's right. The first two episodes are called "The Six Thatchers" and "The Lying Detective." That second one isn't such a surprise, given that we already know that Culverton Smith will play a large role in season four — and he first appeared in "The Dying Detective," in which Sherlock up and fakes having contracted a fatal illness. But what could that first one allude to?
Our friends across the pond at Den of Geek UK note that the closest original Holmes story (at least in title) is "The Adventure of the Six Napoleons," a Lestrade-heavy case in which busts of the French leader are at one point smashed in the search for a missing pearl. Might Lestrade finally get to step into the spotlight for an episode this season? Given that there are only three and this would be the season's first outing, it doesn't seem so likely, but you never know!
Moffat also teased that the first two episodes would be 60 minutes of plot and 30 minutes of drama, whilst the final episode would be a whole lot more plot.
The first two episode titles line up with the three, one-word episode teases Moffat and Gatiss gave us at San Diego Comic Con: Thatcher, Smith, and Sherrinford.
We're still waiting to hear about Sherrinford, which, for us, was the most exciting name to hear, as Sherrinford Holmes is the sometimes-imagined older brother of Mycroft and Sherlock. Given that the Holmes' brothers mentioned another sibling in season 3's His Last Vow, this is most likely the person they were referring to.
Could Sherrinford be the key to understanding the mysterious "Redbeard" references? Though Redbeard has been previously explained as Sherlock's childhood dog, we think there might be more to the reference than meets the eye. As we know from previous interviews, Moftiss have refused to tell Vertue who Redbeard is in the past, with Moffat emphasizing that the Redbeard-as-dog we saw before was "in a dream." Will we be meeting another Holmes' brother in the third episode of season 4?
A lengthy interview with Steven Moffat, Mark Gatiss and Benedict Cumberbatch over Collider gives some more detail about the darkness of season 4. In it, Moffat and Gatiss tease the unique-ness of season 4 villain Culverton Smith, played by Toby Jones. Moffat teased:
He's completely different [to the villains that have come before]. It’s a completely different character. He’s the darkest villain we’ve had. There was always something charming and engaging about Moriarty. There was something fascinating and actually amoral, rather than immoral, about Charles Augustus Magnussen. This guy is the purest evil. Sherlock is actually appalled by him. He's the most evil villain we’ve had. I don’t think that when you see it, you will disagree. He's horrific.
Gatiss added:
It's an interesting thing to chart. We made our Moriarty very different to Doyle's. He’s Irish, and he brings all his charm, his twinkle and his humor to it while he’s also terrifying. Magnussen was a very blank, chilling business man. He doesn’t see what he’s doing as evil. Toby is doing something very interesting. She's an avuncular, funny seeming man with terrible teeth. We've given him terrible teeth, which are symbolic of the rot inside him. It's a great complex, shaded character. You’re not quite sure what the relationship is with him.
For more information about the character of Culverton Smith, check out our on-screen guide to the Sherlock Holmes character tracking his appearances over the last century.

Sherlock Season 4 Release Date
Given that Sherlock just started filming again, we're going to have to wait a while for season 4 to premiere. However, it seems a safe bet to guess that Sherlock season 4 will premiere in January 2017, following the template set by season 2, season 3, and The Abominable Bride.

Sherlock Season 4 Cast
Toby Jones has been cast as a villain in the second episode of Sherlock season 4! As far as we're concerned, this is good news for fans of Toby Jones, fans of Sherlock, and fans of villainous characters in general.
Jones is a well-known character actor who is perhaps most famous for his nefarious role as Dr. Arnim Zola in the Marvel Cinematic Universe — specifically Captain America: The First Avenger and Captain America: The Winter Soldier.
Who will Jones be playing in Sherlock season 4, episode 2? Well, according to Steve Moffat (via the BBC), Jones will be "bringing to life one of Doyle's finest villains." You have roughly seven months to speculate who that might be...
There's been no hint that there’s been any change to the core personnel, including: Benedict Cumberbatch, Martin Freeman, Amanda Abbington, Una Stubbs, Louise Brealey, Rupert Graves, and Jonathan Aris. Technically speaking, there should also be a baby in there somewhere.
The major question mark hangs whether a certain Andrew Scott will be back in the role of Moriarty. Gatiss and Moffat have said that Moriarty is absolutely dead, but have been less forthcoming on whether or not Andrew Scott would be returning — perhaps as a part of Sherlock's mind palace? After all, "The Abominable Bride" confirmed what we discovered in "His Last Vow," which is that Moriarty is a fixture in Sherlock's mind palace — at least when he is drugged. Moffat has teased: "I think what we can say is we may or may not see more of Andrew Scott as Moriarty," Moffat teased.
Daniel Hoffmann-Gill recently announced via Twitter that he would be appearing in the Sherlock season 4 premiere. Hoffman-Gill appeared in Doctor Who's season 9 prequel "The Doctor's Meditation" as Bors.
According to Cultbox, the aptly-named James Holmes will be appearing in the Sherlock season 4 premiere as someone named "Passenger." Holmes (the guest actor) is best known for his role as restaurant owner Clive in BBC sitcom Miranda.
Also according to Cultbox, Sacha Dawan will be appearing in Sherlock season four. He will be playing a characer named AJ. If you are a Moftiss fan, you might remember him from An Adventure in Time and Space, the Mark Gatiss-written docu-drama about the launch of Doctor Who. Dawan played early Who director Waris Hussein.
Sherlock Season 4 Trailer
The first trailer for Sherlock season 4 has arrived and it's action-packed and very mysterious. Check out the full teaser below, then speculate what it might all mean with our trailer analysis...
Sherlock Season 4 Images
We've got a brand new official promo image from Sherlock season 4 to add to the previously released dog-related one. It is not only beautiful, but also seems to tease the idea that John will be distracted in the upcoming season. While Sherlock is his usual focused, demanding self — staring the viewer down — John has off-screen things to worry about. Perhaps his wife, perhaps his child, probably a million things. But he is still standing beside Sherlock, which suggests that — despite his many other worries — his commitment to his best friend still stands.

Previously, we also got this promo image of Sherlock making nice with a dog, presumably for a case. At SDCC, Amanda Abbington teased that she will be in this scene, as well, as Mary. Apparently, the dog was not very cooperative. He was meant to lead Sherlock and Mary along on the trail of a clue. However, he would not move, so Mark Gatiss and Steven Moffat had to re-write the scene on the set in order to accomodate the dog's immovability.

Sherlock Season 4 Episode Guide
We now have the first two episode titles of Sherlock season four: "The Six Thatchers" and "The Lying Detective."
We may not yet know what the Sherlockexactly what the season 4 premiere will be about (though we know the script was penned by Mark Gatiss), but we do now that American (female!) director Rachel Talalay will be directing the first episode of the three-part season.
This is great news. Talalay is a phenomenal director. If you're looking for examples of her recent work (though her resume, in general, is quite prolific), might I suggest checking out the two-part season finale of Doctor Who season 9? It's a masterpiece. (Talalay also directed the two-part finale of Doctor Who season 8.)
In a post-"Abominable Bride" interview, Gatiss spoke about the relative light-heartedness of season 3, implying that the first episode of season 4 might be less-so for Sherlock, John, and especially Mary, saying:
We did make [episodes] one and two [of season 3] actually more light-hearted because we knew he was going to shoot Magnusson, and we deliberately set out to make it like the best times for the three of them as a new team, that they would really have a great time. And the special really does bridge that in so many ways. Even though Mary is very proactive and a huge part, it's a sort of breathing space between 'Vow' and the next one.
Guys, we're really worried about Mary...

Sherlock Season 4 Synopsis
As expected, series three will indeed be "three stand-alone films, 90 minutes each, and an ongoing mystery, as there sort of always is" confirmed Moffat. BBC released this official (somewhat vague) synopsis for the goings-on of Sherlock season 4:
[Season 4] begins with the nation’s favourite detective, the mercurial Sherlock Holmes, back once more on British soil, as Doctor Watson and his wife Mary prepare for their biggest ever challenge – becoming parents for the first time.
Mark Gatiss and Steven Moffat had this to say about the season in an official press release:
Sherlock series four - here we go again! Whatever else we do, wherever we all go, all roads lead back to Baker Street - and it always feels like coming home. Ghosts of the past are rising in the lives of Sherlock Holmes and John Watson bringing adventure, romance and terror in their wake. This is the story we’ve been telling from the beginning. A story about to reach its climax...
Sherlock Season 4 Story & Themes
At SDCC, Cumberbatch teased season 4 of Sherlock, saying: "It's a genuine emotional roller coaster this series." ("With jokes," Vertue added. There are always jokes.) Gatiss echoed the sentiment, saying of the series as a whole: "We've just tried very hard over the last six years to keep it evolving ... You've got to put the characters through the emotional wringer. You can't just have story-of-the-week."
Abbington added: "[Season 4 is] really dark. It's the darkest that Steven and Mark have written ... When we read them, all of us, we were kind of overwhelmed by them, because they were shocking and amazing, as they always are. But, if we can pull this off, it's amazing."
In that same post-"Abominable Bride" interview, Gatiss and Moffat spoke about how much of the joy in writing Sherlock comes from fleshing out those quieter, sometimes domestic moments that wouldn't have made it into Sir Arthur Conan Doyle's stories. Gatiss teased:
Being in the middle of writing series 4 at the moment, if anything is like a good writing exercise for the show, is to look at the stories and think, 'What did Doyle not do in terms of what must have gone on.' If you have two men living together, at some point, even if you back-project, he would have asked him, 'Have you ever um…' ... You look at a story you’re very familiar with and think, I wonder what else happened in this domestic situation that we were never privy to.
Could this mean we'll be getting more John and Sherlock domestic moments in season 4? Perhaps, Gatiss elaborated on his comments, referencing John asking Sherlock to be his best man as an example of something Conan Doyle didn't write about, but that makes sense within the context of the BBC adaptation.
When talking generally about the themes and story for the season, Moffat mysteriously teased: He mysteriously added: "I think there's still an ongoing element that people haven't really picked up on." Time for a Sherlock season one through three rewatch? Always.
Sherlock Season 4 Villains
We know which classic Sherlock Holmes villain Toby Jones will be playing in Sherlock season 4: Culverton Smith.
Smith originally appears in Sir Arthur Conan Doyle's 1913 story "The Adventure of the Dying Detective." He is a villain who uses tropical infectious diseases to murder. In the Conan Doyle story, he murders his nephew in this manner, attracting Sherlock's suspicions. Thus, he sends Sherlock a spring-loaded box capable of infecting those who open it with a deadly diseason.
The story begins when John Watson is called to check on his friend Sherlock Holmes, who has apparently contracted a grave disease. (As Mrs. Hudson informs Watson, Holmes hasn't eaten for three days.) Of course, Sherlock is faking to draw a confession out of Smith, something he manages, but not without seriously worrying John in the mean time — a character-driven plot Sherlock could have a lot of fun with.
"The Adventures of the Dying Detective" is set in Watson's second year of marriage, which implies Mary Watson will still be alive and well in the second episode of season 4. (Yeah, we're still worried about her, though.)

Sherlock Season 4 Directors
We've already mentioned that the fabulous Rachel Talalay is confirmed to direct the first episode of Sherlock season 4. We know now that Nick Hurran (Sherlock's "His Last Vow,"Doctor Who's "The Day Of The Doctor") will be directing season 4, episode 2, which just begun filming.
Benjamin Caron will be directing the Sherlock season four finale, per this Instagram announcement. Like Talalay, Caron has never before directed an episode of Sherlock, but he has stepped behind the camera for shows like Skins, My Mad Fat Diary, The Crown, and Wallander. It will be interesting to see what Caron brings to Sherlock.

Sherlock Season 4 Writers
Some combination of Steven Moffat, Mark Gatiss and Stephen Thompson have been responsible for every Sherlockscript so far, and we see no reason why that should change for series four.
We know for sure that Mark Gatiss has penned the script for the season premiere, just like last season's "The Empty Hearse."
Sherlock Season 4 Rumors & Speculation
It sounds like Sherlock season 4 may be heading to Morocco for filming. HuffPost Morocco first reported that Sherlock would be filming in Marrakesh "soon." And at Sherlocked UK, Mark Gatiss shared that he and Steven Moffat did some of their writing for season four in the country...
Can anyone think of any iconic Sherlock Holmes story set in North Africa or the Middle East?
Off to top of my head, my chief speculation is that the desert country could be used a stand-in for Afghanistan, where John Watson served in the military before returning to London after his injury. Could we be getting flashbacks to John's time at war, or, perhaps, a return to the war-torn region for our detective heroes?
Or, perhaps, Morocco will be used as a stand-in for Pakistan, aka the place we last saw Irene Adler. At the end of "A Scandal in Belgravia," we see Sherlock going to Karachi to rescue Irene from execution. Is she still there? Could the Morrocan filming mean a return for Irene Adler? This is all just speculation, of course. We'll have to wait and see...
The Sherlock production team is skilled at keeping secrets. When Amanda Abbington asked Moffat and Gatiss if there are things they hadn't told the cast in the post-"Abominable Bride" interview, Moffat said: "There's loads we're not telling you." Sometimes, the showrunners even avoid writing important pieces of dialogue down to limit the chances of others finding out about it. Moffat said: "There's one coming up in this series where we just agreed this will never be written down."
Much of the major speculation in regards to Sherlock season 4 (with its basis in off-stage canon) is that it will include the death of the recently arrived Mary Watson, played by Amanda Abbington. Steven Moffat's prediction that "it all goes to hell" for John and Sherlock in season four would point vaguely in that direction. Asked what the theme of season four would be, Moffat said:
It's consequences. Chickens come home to roost. It's dark in some ways - obviously it's great fun and a Sherlock Holmes romp and all that - but there's a sense of things coming back to bite you. It's not a safe, sensible way to live. It's hilarious and exhilarating some days, but some days it's going to be bloody frightening.
Who'll be providing the fright, we wonder? Could that "miss me?" cliffhanger have something to do with it? Or are there more terrifying villains from canon in store? It's not only being frightened that Sherlock fans have to worry about, but also being put through the emotional wringer.
We're certainly going to put them through the mill. It's going to be more of an emotional upheaval. Hopefully enjoyable and fun, all the things Sherlock must always be. It will be tough at times. Maybe that's the word? A tougher series.
John and Mary Watson's relationship is a keen bet among some fans for providing some of the emotional toughness Moffat is hinting towards here, a notion the showrunner doesn't dissuade us from by saying "John's got a wife and Sherlock likes her and isn't it adorable, and then it all goes to hell. Remember where we left them." Shall we just start the #SaveMary campaign now?
Much season 4 speculation also surrounds the mysterious Redbeard, depicted as Sherlock's childhood dog in season 3. In "The Abominable Bride," Sherlock murmurs "Redbeard" at the sound of an approaching dog, and we see it prominently written in Mycroft's notebook. When asked directly about who or what Redbeard might be, Gatiss and Moffat refused to answer (which, to be fair, they do with pretty much any specific question regarding season 4).
"Well, they won't tell me, so they're certainly not going to tell you," producer Sue Vertue adds in the post-"Abominable Bride" interview. Moffat does comment that, when we see Redbeard as a dog in season 3, "it was a dream." Do with this information what you will, folks.
Sherlock: #Setlock
Back (again) pic.twitter.com/aY5P39vIqJ
— Mark Gatiss (@Markgatiss) April 20, 2016
Back 4 (more) #Sherlockpic.twitter.com/jfTCE1e9FU
— Mark Gatiss (@Markgatiss) April 21, 2016
Back! #Sherlockpic.twitter.com/WFvpGpy3PV
— Mark Gatiss (@Markgatiss) April 11, 2016
Back 2. #Sherlockpic.twitter.com/iRAHPm5kDC
— Mark Gatiss (@Markgatiss) April 13, 2016
Sherlock production designer Arwel Wyn Jones has been sharing some fun photos from the set, including a short of director Rachel Talalay and the Episode 2 script...
There's someone new in the chair today @rtalalaypic.twitter.com/esqknyccCq
— Arwel Wyn Jones (@arwelwjones) April 18, 2016
Today's work, breakdown & budget this... #lovemyworkpic.twitter.com/uZQj7b2i5w
— Arwel Wyn Jones (@arwelwjones) April 9, 2016
Is there anyone home? pic.twitter.com/n62KOhcDPW
— Arwel Wyn Jones (@arwelwjones) April 15, 2016
Little morning treat %uD83D%uDE09 pic.twitter.com/pYeHuLlZUx
— Arwel Wyn Jones (@arwelwjones) April 14, 2016
And here's a shot of some of the cast — Cumberbatch, Freeman, and Rupert Graves (Lestrade) — with some visiting students to the set...
Thanks @hartswoodfilms& Sherlock crew for inspiring our young filmmakers & supporting the work of @intofilm_edupic.twitter.com/hTLEjy0zeT
— Non Stevens (@non_intofilm) April 20, 2016
We will continue to update this Sherlock news hub with information as we receieve it. Check back periodically for new details about Sherlock season 4!