Benedict Cumberbatch has addressed uncertainty over the future of Sherlock.
Cumberbatch and Martin Freeman started shooting the new series in May, joined once again by Amanda Abbington as Mary Morstan, as well as by a new villain played by Toby Jones.
Cumberbatch joined Abbington plus the show's co-creators Steven Moffat and Mark Gatiss for a panel at Comic-Con in San Diego last month (July 24), when he was asked how long the show could keep going for.
"We’ll see. We’ll see how this series lands," Cumberbatch responded, as reported by Collider.
"It’s been great fun to come back and do it. How it will continue in the future, who knows? It’s not just about what any of us want. It’s about what’s actually right for the show, to be honest, and that has to be judged very carefully."
Cumberbatch continued: "Think about the very limited but classic British output of certain shows, and there aren’t that many of them. It’s a painful thing to say, but maybe Series Four is it. Who knows? I don’t know. I don’t want to say this is it because we have too much fun doing it. But generally, we have to see how this lands."
"And the actors aren’t the only ones who are busy," he added. "Mark and Steven are pretty tied up. Mark is an actor, as well as a producer and writer. It’s all of us being stretched in different directions. Also, this has run longer than most American series. You don’t want to compromise it by continually doing it, just because we could carry it on. There’s lots of stuff to weigh. It’s not just about what we want to do. It’s about what’s right. We’ll see. Really, we will have to see. No one has decided on it, so there’s no yes or no to an end or a beginning."
Steven Moffat went on to say: "We have to take it one season at a time. We don’t know what the future will be, and it’s not entirely down to us. Hopefully, we’ll do more. I find it hard to imagine that we won’t. But in terms of a specific plan, there are ideas that we haven’t gotten to yet."
During the panel, Abbington told fans of the new series: "It's really dark. It's the darkest Steven and Mark have written."
The BBC has previously revealed that series four will begin with Cumberbatch's title character "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".
Cumberbatch and Freeman returned in a one-off special, Sherlock: The Abominable Bride, on New Year's Day this year. The special attracted an audience of 11.6 million viewers, making it the most-watched programme of the 2015-16 festive season.
The show's last series, which also consisted of three episodes, aired in 2014. Cumberbatch and Freeman first played Doyle's iconic characters in 2010 and each actor has won an Emmy for his performance.