"Sherlock" season 4 is still a go but at some point, showrunner Steven Moffat never thought he would do one more run with leads Benedict Cumberbatch and Martin Freeman. The two actors had to be persuaded to reprise their roles in the contemporary remake of the Arthur Conan Doyle classic. 

"They don't need Sherlock anymore. So we have to persuade them to do it - which is fair enough," he revealed to Newsbeat during the BAFTA TV Awards nominee party. 

Cumberbatch, for one, has become very busy. His schedule is chock-full of commitments, both for movies and in theatre. The 38-year-old actor was also close to winning an Oscar in this year's Academy Awards, thus he has a lot going on at the moment. 

But despite the hectic timetable, Cumberbatch is still onboard and Moffat is happy and thankful about it. The same goes for Freeman, who stars in the BBC detective drama as Sherlock's loyal companion and right hand John Watson. 

"They are very serious about it. They do love it very much. I didn't think we actually thought we'd get a fourth series out of them," he went on to say, adding that their agreement for another run surprised him in a pleasant way. 

Unlike other series, the show only runs three episodes in one season, and viewers need to wait two years to see the detective in action. Moffat believes in the ardor of the fans who will always be waiting to see Sherlock come back, crack cases, and boot criminals to prison.

The executive producer has already dished out plans for season 5. However, it remains to be seen if the actors' schedules will get in the way. 

For now, Moffat, declaring himself an optimist, shared, "Sherlock can go on a long time because we just show up occasionally and do it. It's like a reunion party every time." 

A Christmas special of "Sherlock" was already filmed and will be aired by the end of the year. Season 4 of the BBC drama will debut next year.