Sherlock‘s upcoming one-off special has started filming in Bristol.

Written by the show’s co-creators, Mark Gatiss and Steven Moffat, the special sees Benedict Cumberbatch return as Sherlock Holmes, alongside Martin Freeman as John Watson and Amanda Abbington as Mary Watson.

Rupert Graves (Lestrade) and Jonathan Aris (Anderson) were also spotted filming today.

There have not yet been any sightings of Andrew Scott as Moriarty. The actor was recently cast in the new James Bond movie, SPECTRE, which is currently filming in Austria.

> Here’s everything we know about the special and Season 4 so far.

Writer Mark Gatiss tweeted a photo of the special’s clapperboard earlier today, with the caption: “Element-hairy, my dear Watson!”

Directed by Douglas Mackinnon, the special is expected to air next Christmas on BBC One.

Gatiss recently hinted that a crossover featuring Sherlock Holmes and the Doctor “may be possible”.

> Buy the complete Season 1-3 boxset on Amazon.

 What do you hope to see in the special? Let us know below…