Not for the first time this year, Tom Hiddleston has been at the centre of MUCH internet speculation, after he was linked with a role in Sherlock series 4.

The Night Manager actor is rumoured to be joining the show as the third Holmes brother alongside Benedict Cumberbatch and Mark Gatiss - and now BBC Store has put together a cheeky video imagining exactly what that would look like.

preview for Sherlock: Tom Hiddleston as the third Holmes brother!? Not quite

It's a great clip, and Tom would clearly be a popular addition to the show - but could he be appearing on the drama for real?

Tom posed with Sherlock stars Mark Gatiss and Amanda Abbington for pictures at San Diego Comic-Con this weekend, and fans of the show absolutely lost it online.

Sherlock's third series finale also hinted at the introduction of a third Holmes sibling, with Mycroft's line: "I'm not given to outbursts of brotherly compassion. You know what happened to the other one."

Sherlock series four will air in 2017.

preview for Sherlock teaser for season 4