'Sherlock' season 4 news, updates: Benedict Cumberbatch photographed on set; Fourth installment series' last?

Thousands of fans are gearing up for the supposed return of Benedict Cumberbatch's "Sherlock" for its fourth installment. However, how true are the rumors that the actor has waived off the series, making the upcoming season its last?

The executive producer of "Sherlock," Steven Moffat, recently sat down with The Telegraph for an exclusive interview where he shed light on rumors hounding the stars of the series and its impending fourth run.

According to Moffat, "Sherlock" season 4 could be the last for the hit BBC drama seeing as how Cumberbatch who plays the titular character and Martin Freeman who plays Watson, are both in demand these days. He said as an "internationally renowned actor," Cumberbatch is only doing the fourth season "out of loyalty to its fans."

"I don't know how long we can keep it going. I'm personally willing but I'm hardly the main draw. I would be moderately surprised if this was the last time we ever made this show. But it absolutely could be," he added.

No further details have been revealed about the fourth installment, although Toby Jones has been tapped to play the role of the villain. Nevertheless, Moffat said that the upcoming season would make use of Conan Doyle stories that are not as well known as his other stories.

The Sydney Morning Herald observed that Sherlock and Watson were last seen in January in a Victorian-themed special for "Sherlock" titled "The Abominable Bride." BBC noted that the said episode was, by far, the most popular of all, which is probably why it nabbed six Emmy nominations this year, including best TV movie and lead actor in a limited series or movie.

According to Den of Geek, "Sherlock" season 4 started filming in April. Nevertheless, there is no confirmation as to how all three stories of the series will be filmed. The stories could be filmed in one uninterrupted block or they could be filmed with brief intervals to accommodate the busy schedule of Cumberbatch and Freeman.

"Sherlock" season 4 is expected to hit the air in 2017.