Since "Sherlock" season 4 didn't really leave any questions left unanswered, many wonder whether co-creators Steven Moffat and Mark Gatiss plan to continue the BBC series. However, the choice doesn't seem to be up to them.

Moffat and Gatiss may be the creative minds behind the show, but the ultimate fate of the show lies in the hands of its star, Benedict Cumberbatch. "Sherlock" arguably shot the actor's name to mainstream fame in 2010. Cumberbatch has since been busy with other projects, including Marvel's "Doctor Strange," "The Hobbit" trilogy, and "The Imitation Game," for which he earned an Academy Award nomination for Best Actor. And it's precisely because of his demanding schedule that rumors of the show's cancellation have been rampant.

"We couldn't do it without him, of course not," Gatiss told the Daily Star. "It's a special thing and we couldn't do it without Benedict. We're very lucky to have the keys to Baker Street at the moment."

It looks like the future of "Sherlock" relies on Cumberbatch's go-ahead. But should the series continue to a fifth season, Moffat and Gatiss already have a few classic Arthur Conan Doyle stories lined up.

"Mark's always wanted to do 'The Red-Headed League,'" Moffat revealed to Vulture. "There's 'The Engineer's Thumb,' which is a slightly mad story that doesn't have a proper ending. There's an element of 'The Greek Interpreter' that I think is really exciting, which hasn't been done, because in our version of events Irene Adler is still out there. There's always that."

Additionally, Moffat previously explained that season 5 will see the dynamic duo, Sherlock Holmes and Dr. John Watson (Martin Freeman) going back to their roots: solving seemingly impossible cases from the comfort of their flat — which was already glimpsed in the final minutes of "The Final Problem." However, fans have noted that the season 4 closer had a certain air of finality to it, which leaves the future of the show uncertain.