'Sherlock' Creators Discuss Season 4 Planning, Social Media

Steven Moffat and Mark Gatiss say they would love to continue the BBC hit show with Benedict Cumberbatch and Martin Freeman for a long time, but getting everyone together is a challenge.

LONDON -- The storylines of season four of BBC hit show Sherlock are already broadly mapped out, co-creators and writers Steven Moffat and Mark Gatiss said here Tuesday night.

After season three of the detective series aired on the BBC early in the year, the fourth season is expected to be ready for 2016, but no official airdates have been announced.

Speaking at an event organized by the Royal Television Society, Gatiss said he and Moffat have mapped out "what will happen in the next season" of the show, starring Benedict Cumberbatch as Sherlock Holmes and Martin Freeman as Doctor Watson. But he said those plans will "get more detailed" as production for the next three-episode season draws nearer.

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Asked if they see the show continuing long into the future, Gatiss said: "The idea of growing older with it would be great. But it is hard to get everyone back together, because they have become extremely famous -- except for us." The remark drew laughs.

Moffat, who is currently working on the first Doctor Who season with Peter Capaldi in the lead role, echoed that the writing duo sees enough material from the original Holmes stories that could be addresses and modernized.

While they dropped no specific hints about the fourth season, Moffat and Gatiss confirmed that Holmes' arch enemy Moriarty (Andrew Scott), who was revealed to be alive at the end of the third season, would be featured in the new season. They said his return was not added last-minute due to fan demand, but they had long planned it.

Meanwhile, the show is also likely to see increased roles for female characters Molly Hooper (Louise Brealey) and Mrs. Hudson (Una Stubbs), the creators said. They also hinted that new female characters could be added.

Gatiss said that as the show continues, "It's about keeping it new" and introducing new characters, as well as continuing "Sherlock's gradual humanization."

During the Tuesday evening event, entitled "Sherlock -- Anatomy of a Hit," Moffat recalled that he didn't have high expectations for ratings when he started the show. "I thought it would be a little niche show that would win an award in Poland," he said.

Added Ben Stephenson, controller of drama commissioning at the BBC: "Did we know we had a phenomenal hit? No."

He recalled that when he and his team watched the original 60-minute pilot for Sherlock, they concluded: "There was just something about it. We actually controversially, according to newspapers, decided not to show it," but wanted to reshoot a 90-minute version and do a three-episode first season.

Asked if they cast Cumberbatch to get a star, Moffat and Gatiss said he was a respected actor, but not yet a star at that time. They said the creators and BBC executives had Cumberbatch in mind and loved his performance when he did his first reading.

Stephenson said: "Nobody had a clue who he was. I did." He added: "Great shows are not about stars, but about great shows. And they make stars."

The BBC executive said he has often been asked why the first season of Sherlock launched in the summer, explaining that this shouldn't be seen as the U.K. public broadcaster not giving the detective series proper support. "The autumn is not better," Stephenson said. "There are not more people available to watch."

The role of social media, including Twitter, in the creative writing process for TV was also part of Tuesday's discussion. Gatiss and Moffat said that they used all the fan discussion -- on social media and elsewhere -- about Holmes' fall from the roof of a building at the end of season two as inspiration to present different versions of what could have happened early in season three.

Does Twitter affect Sherlock storylines? "It can't," Moffat said, emphasizing that creatives must focus on their stories and can't constantly look for input on social media.