Sherlock: I thought they'd lost the plot

Dr Watson and Sherlock Holmes

Sherlock's back on TV for New Year's Day with a one off special called The Abominable Bride.

It's not set in the present day, as usual with the series, but back in the original setting of Victorian times.

A move which Benedict Cumberbatch didn't immediately warm to:

"I thought it was madness."

The episode is also in cinemas for today only - but fans will be treated to extra content.

Benedict took a bit of convincing when the show's writers said they wanted to go back to 1895.

"I thought they had finally lost the plot, jumped the shark, all the other cliches of television gone mad. Then they explained the idea and pitched it to me properly, and I think it is fantastic - absolutely brilliant".

One of the writers, Steven Moffat, says the one-off special is a "treat" for fans.

"We've done a modern version of Sherlock Holmes for three series and it's been tremendously successful. This is a one-off, it's a special and so we have to do something that's a treat"

Just a one off - no more?

No - there is a fourth series on the way too.

Mark Gatiss, aka Mycroft

Mark Gatiss, who plays Sherlock's brother Mycroft and co-writes the show says:

"We're going to do Sherlock Holmes in the 28th century. It's set in 2914 and Dr Watson isn't in it, he has a robot cat. And they battle Moriarty who is a race of aliens with several Irish heads."

But he's joking!

There will, in fact, be three episodes starring Benedict Cumberbatch and Martin Freeman, despite rumours the pair were too busy filmmaking in Hollywood.

"And it will be back to the modern day, we're back to the 21st century for season four," added Gatiss.

Sherlock: The Abominable Bride will be in cinemas for one night only on 1 January and BBC One from 9pm.

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