Ever since the popularity of BBC's TV series Sherlock encouraged the network to make another season, there have been rumors and speculation about the release date which is currently unsure. It was rumored to be ready in 2015 since reports came out that both seasons 4 and 5 had been approved and the creators had developed the ideas for them, but it seems that fans may have to wait until 2016 or even longer before seeing the next season since the crew, cast and actors are having problems meeting between all the difficult scheduling conflicts.

After the commercial success and popularity of the Sherlock series became widespread, the lead actors Martin Freeman and Benedict Cumberbatch have become very much in-demand. So much so, that with both actors busy with other film assignments Sherlock has been put on the back burner, resulting in a complete delay of the filming of Season 4. The shooting schedules of Season 4 will have to be aligned with the busy schedules of both Freeman and Cumberbatch before any progress is made.

Apart from these two, director Moffat is also busy with the eighth season of Doctor Who, featuring Peter Capaldi in the lead role. Despite their busy schedules, Moffat took time to talk with Cumberbatch, informing him that Sherlock Season 4 will certainly continue and the show doesn't see an end date.

The Hollywood Reporter wrote that fans can expect the entrance of more female characters in Season 4 like Una Stubbs as Mrs. Hudson and Louise Brealey as Molly Hooper. It was reported that the executives at BBC are planning to have a "Sherlock Christmas Special" to take advantage of its popularity. Sherlock Season 3 was one of the most watched drama series in the past 10 years, gathering an average of 11.8 million viewers during its January screening in the U.K. alone.

The series also won Cumberbatch the "TV Detective" award during the National Television Awards for his role playing the strange super-sleuth. He was rumored to have been tapped by director Sergei Bodrov in the new crime thriller movie Blood Mountain. He was also voted as the "Sexiest Movie Star in the World."