BBC 'Sherlock' Season 4 Air Date & Premiere: Stand-Alone Christmas Special Episode Being Filmed, Trailer Released [WATCH]

Benedict Cumberbatch (Sherlock Holmes), Martin Freeman (Dr. John Watson) and the rest of the gang has gotten back together for the production of the stand-along special episode of "Sherlock," expected to air on Christmas, Dec. 25.

The Coston Hall in Bristol, England and the other parts of England will be the show's playground for the next coming weeks, as the cast and crew bring Stephen Moffat and Mark Gatiss' script to life.

During the episode, Sherlock, who's in an investigative mood, will likely use his skills as a sleuth to finally learn if the treacherous Moriarty is, in fact, dead. Moriarty's "death" during the Season 3 finale of the series only rang as false to many viewers. And Gatiss assured the public during an interview with to Radio Times that the special episode would "completely" solve Moriarty's reemergence mystery.

Rumors are still flying about the possibility of the already mapped-out Season 4 premiering during January 2016, as originally announced. Some have said the series will premiere in January as planned. However, the cast is continuously busy.

Newlywed Cumberbatch is preparing to be a new dad; he's wrapping up his stint filming "Doctor Strange"; and he dealing with the recent slew of award shows that look to honor him for his role as Alan Turning in the film "The Imitation Game," which is about cracking the Enigma Code.

Enthusiasts are only 10 months from seeing 38-year-old Cumberbatch wear the signature coat, cape and deerstalker cap that Sir Arthur Conan Doyle's most iconic character Sherlock his known for. And let's not forget Freeman, who fans will see wearing a king-sized mustache, a bowler hat and a cozy scarf as he portrays Dr. Watson.

See the trailer for the upcoming episode below: