Benedict Cumberbatch, Martin Freeman and the other cast reprise their roles on Sherlock's fourth season. It is reported that they have already started filming the Christmas Special at Bristol within the Colton Hall cellars
Co-writer Mark Gatiss tweeted on Monday that he was on his way to start filming and posted on Twitter "On my way West. It begins...#Sherlock" on the social media site.
Cast including Benedict Cumberbatch and Martin Freeman were snapped arriving at Colston Hall in Bristol where they were swiftly ushered inside through a side door leading to the cellars of the music venue, reports SWNS. Hypable also adds, "Fans who are trying to catch glimpses of the Sherlock filming say that there are many extras dressed in Edwardian clothing. That, coupled with the fact that Watson is sporting a mustache and Sherlock is wearing a bowtie, means this is going to be one of the most unique episodes of Sherlock we've seen so far." BBC also officially confirmed through Twitter that filming has been started and hinted that a character may sport a new moustache.
"Element-hairy, my dear Watson! Filming is now underway on the #Sherlock Special, coming to @BBCOne in 2015," the BBC tweet read.
As previously reported by Hollywood Reported, Steven Moffat has dished out in an interview that the special will be based on the "The Adventure of the Blue Carbuncle," one of the 56 short stories written by Sir Arthur Conan Doyle for his Sherlock Holmes series.
In addition, Moffat told Entertainment Weekly that the upcoming season will be darker and devastating.
"We have a plan to top it," he said.
"And I do think our plan is devastating. We've practically reduced our cast to tears telling them the plan ... we're probably more excited that we've ever been about Sherlock."
After Sherlock's Christmas special, BBC will start airing its first episode on January 2016.
You may check some snapchats at the Bristol
here.