Steven Moffat has revealed that the new season of Sherlock will feature a “shift in tone” from previous episodes.

Benedict Cumberbatch and Martin Freeman will return to BBC One this Christmas for a one-off special set in 1895, followed by a fourth season of three new episodes at a later date.

> Pre-order the Sherlock special on DVD on Amazon.

Speaking at Comic-Con in San Diego, Moffat told DS: “We’ve got a clear idea what we’re going to do [in Season 4] and it’s going to be another shift in tone.”

He hinted: “Yes, there’s going to be some dark stuff coming, there always is, [but] there’ll also be lots of fun and jokes and detection and all that nonsense.”

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

Season 4 is expected to begin filming later this year.

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

What are your hopes for Season 4? Let us know below…