Sherlock and Watson
Sherlock and WatsonFacebook/Sherlock

The shooting for the much-awaited "Sherlock" Season 4 has begun, to the excitement of numerous fans all over the world. Although a release date has not been confirmed yet, this news promises an early- to mid-2017 release of the season, which is pegged to be the final one in the BBC One series.

The "Doctor Strange" star Benedict Cumberbatch has also said that the wait will not be too long. According to Coming Soon, Cumberbatch said that he was "genuinely thrilled to be back filming 'Sherlock' with all the cast and crew. I can't wait for everyone to see season four. But you will have to wait, though not for long. And it will be worth it."

Potential Spoilers Ahead

Meanwhile, this news has given momentum to the plethora of fan theories regarding the upcoming Season 4. One of the most popular theories, or at least hopes, is that Molly (Louise Brealey) and Sherlock might get a romantic storyline. Even if that comes true, the next theory about Sherlock's imminent death in the season will put a bump in their romantic future.

A more realistic yet sadistic fan theory for "Sherlock" Season 4 is the death of Watson's (Martin Freeman) wife Mary (Amanda Abbington) during childbirth. The season is expected to be a dark and twisted one, after all.

Another more exciting rumour is about Tom Hiddleston joining the cast as the third Holmes brother. Lifestyle One points to Mycroft's (Mark Gatiss) cryptic quote from "Sherlock" Season 3, where he says, "I'm not given to outbursts of brotherly compassion. You know what happened to the other one," to suggest that Hiddleston could very well be the "other one."

The addition of Daniel Hoffman-Gill to the cast, on the other hand, has already been confirmed. He will play the role of Gold Teeth, but his intentions and allegiance remains a mystery as of now.

The wait for Season 4 may yet be a long one, but you can watch while the time away with the set photos from Season 4 of "Sherlock:"