Sherlock Season 4 has begun production
Sherlock Season 4 has begun productionFacebook / Sherlock

While fans are eagerly waiting for the next season of BBC's "Sherlock," recent reports suggest that Season 4 of the hit TV series based on Arthur Conan Doyle's detective stories of same name has already started to shoot in Morocco.

According to Christian Post, several leaks from the production set have revealed teasers for the next season. "Sherlock" is known for having long gaps between the seasons and fans are looking forward to find the further adventures of Sherlock and Watson once Season 4 returns.

As hinted by the leaks, Toby Jones' character of Culverton Smith will be the new antagonist of the series. Smith is one of the most prominent villains in the original novels and Sherlock fans, who have read Doyle's stories, know that Smith spreads a deadly plague, intending to kill Sherlock.

However, in the stories, Sherlock finds a way to prevent the disease from infecting him by pretending to be sick in order to lure Smith and get him arrested. Though the series takes influence from the stories, the plot is significantly changed and modified to suit the contemporary audience. Hence, it is not yet revealed that how the story will unfold in the upcoming season.

Apart from Jones' addition, several speculations state that Sherlock's archenemy, Moriarty (Mark Gatiss), will also make a comeback in Season 4, making things pretty difficult for Sherlock (Benedict Cumberbatch) and John Watson (Martin Freeman).

Though Moriarty died in Season 2, the show-runners of the show have hinted that there are "ghosts" of past that will continue haunting Sherlock and Watson. Christian Post has also hinted that the new antagonist might have some connections with Moriarty or he might be manipulating Moriarty's name to threaten Sherlock and Watson.

"Sherlock" Season 4 will play a key role in the entire franchise as several characters from the previous seasons will be returning and Sherlock might find a love interest too. Fans are also curious to find the details of this love interest and are speculating that it might be none other than Irene Adler (Lara Pulver), who appeared in Season 1.

Though there hasn't been any official release date yet, "Sherlock" Season 4 is expected to premiere in early 2017.