"Sherlock" Season 4 is coming in 2016, with a Christmas special in 2015. With a long wait between seasons, in part becasue that is how the show has always done it, and in part because the actors involved are getting very famous and busy, there have been a lot of rumors and speculation about what to expect from season 4. Here is a roundup of all the best rumors and speculation out there right now. 

Showrunners Steven Moffat and Mark Gatiss further shed light to the rumors surrounding the return of Moriarty.

"We've had what we're going to do with Moriarty in place from before the second season. Exactly what we're going to do. I remember talking it through with Andrew Scott, who plays Moriarty. Wait and see what's going to happen," Moffat said.

However, producer Gatiss made affirmations that despite the busy schedules, they are still working to set a production date.

"I can officially tell you that we are moving closer to agreeing some dates to shoot. If that sounds like a party line, it is. That is proper progress because Ben and Martin and Steven are so busy, but actually trying to get everybody to interlock is ... we have made significant progress," he said.

Fans finally have an inkling of when the BBC will be airing season 4 of "Sherlock." The network has announced that the fourth season will premiere in 2016 and the BBC has further revealed that there will be a one-episode special before the airing of season 4.

In the last few moments of Season 3, Moriarty made a return across computer screens world wide saying "Did you miss me?" so a lot of the speculation centers around him.

"That was [decided] in the cutting room," said Moffat to the Digital Spy. "It was Mark [Gatiss]'s idea to get one more little blip of him, and we shot the live action shot which we hadn't done for the actual show and put that in after the credits. It was just a final little treat, really, to wind people up!"

"I can't really say what we're doing with that, but there is no last-minute whim in this," said Steven Moffat to Vulture when asked about the new twist. "We've had what we're going to do with Moriarty in place from before the second season. Exactly what we're going to do. I remember talking it through with Andrew Scott, who plays Moriarty. Wait and see what's going to happen."

One person who does know what happened to Moriarty is actor Benedict Cumberbatch, who revealed little to nothing about how Moriarty managed to be alive. "I casually choose to forget in order to rediscover it again a little bit," says Cumberbatch in an interview with MTV at Comic-Con 2014. "I like casually forgetting, not least because there's a lot of other traffic between then and now but also because it's more fun because it's slightly more fresh. It's a very good idea, I do remember that detail. I'm just trying not to remember it so I don't blurt it out."

In a webchat with PBS, Gatiss was questioned about how and why the Holmes brothers are so interesting and smart. His response: "Why are the Holmes brothers the way they are? What are their parents like? Maybe we'll see one day. I'd like to find a way of showing, more than we have, that [Mycroft] is actually even cleverer than Sherlock."

In July, co-creator Mark Gatiss -- who also plays the role of Sherlock's older brother Mycroft Holmes --  tweeted, "Series Four! At last! It's always special to return to Sherlock but this time it's even more special as we're doing... a Special! Not only THAT, we'll then be shooting three more episodes which will take Sherlock and John Watson into deeper and darker water than ever before. The whole Sherlock team is terrifically excited to return for four new adventures. The Game is on - again!"

Again, "Sherlock" season 4 is slated to return in BBC on its usual three episodes airing in 2016. Prior to that, a Christmas Special in 2015 will be release