'Sherlock' Season 4 Air Date, Trailer & Update: Sherlock, Watson meet 'The Abominable Bride' in Victorian Christmas Special [VIDEO]

A new trailer for the "Sherlock" Victorian Christmas Special has been released and in it, we see Sherlock and John meet "The Abominable Bride." In the 40-second trailer, we meet the titular "Bride" in a wedding dress, a veil over her face and carrying a shotgun.

"The stage is set, the curtain rises, we are ready to begin. The avenging ghost," says Benedict Cumberbatch as Sherlock. Watch the trailer below:

Benedict Cumberbatch stars as Sherlock Holmes with Martin Freeman as Dr. John Watson and in the upcoming special, the two go back to 1895 Victorian London. There they try to solve the mystery of "The Abominable Bride" who the two discover is Thomas Ricoletti's recently-deceased wife. As to why she is gallivanting about and seeking revenge in her wedding gown, we will know when it airs on January 1, 2016.

It is an hour-and-a-half special that will be shown at 9 p.m. ET on PBS in the US and on BBC One in the UK. It will also have a limited release in theaters on Jan. 5, Tuesday and Jan. 6, Wednesday at 7:30 p.m. in the U.S. It will include 20 extra minutes of footage and a tour of 221B Baker Street. According to MTV, it will be hosted by Simon Baker. The special is written by Steven Moffat and Mark Gatiss and directed by Douglas Mackinnon.

In the behind-the-scenes video released by BBC, the cast and crew talked about the upcoming special. Series creator Steven Moffat shared that they made the special because it was "irresistible."

"Part of the impulse came from me and Mark [Gatiss] saying 'Wouldn't it be a shame if we never got to see them do it in the authentic setting?'" Moffat said, as reported by CNET. "So it was irresistible to do a special that is Victorian."

Cumberbatch also shared his views of the special.

"I think Victorian London and all the sort of trappings of that era are endlessly fascinating," the "Sherlock" actor said. "The sort of ghoulish, nightmarish, fog-laden dark corners and alleyways. The dampness the sort of whole kind of claustrophobic night world that he inhabits, it's a masterful lens on that whole era as well."

The video also revealed that Cumberbatch will be playing a more "light" version of Sherlock, a different one from the modern adaptation.

"It's a very affectionate, amusing Sherlock," comments Una Stubbs (Mrs. Hudson) in the video.

Take a look at BBC's behind-the-scenes video: