The BBC's upcoming Sherlock special starring Benedict Cumberbatch and Martin Freeman will be set in Victorian England. A teaser image released earlier this year had hinted as much, with Holmes donning a top hat and Watson showing off a finely manicured moustache.

SherlockBenedict Cumberbatch [L] and Martin Freeman [R] will be back for the Sherlock special

Now, creator Steven Moffat has confirmed the news during an interview with Entertainment Weekly at SXSW, confirming the show will be heading back the 19th century of the original detective series written by Arthur Conan Doyle.

"The special is its own thing. We wouldn't have done the story we're doing, and the way we're doing it, if we didn't have this special," Moffat said. "It's not part of the run of three we could hardly conceal - it's Victorian."

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Moffat added that he and co-creator Mark Gatiss decided it had to be a special to make the show work outside its usual contemporary setting.

"It had to be a separate entity on its own," he said. "It's kind of in its own little bubble."

Moffat added that the special is pretty much finished and that he's pleased with the final result. Still, the BBC is delaying announcing a concrete air date. Speculation suggests that date is likely to be around the Christmas period.

Meanwhile, Cumberbatch was recently announced for the biography-drama Flying Horse, written and directed by Gary Oldman. It tells the story of pioneering photographer Eadweard Muybridge and the courtship and love affair between his wife Flora and Harry Larkyns.

The movie co-stars Ralph Fiennes and Amanda Seyfried and is set for release in 2016.

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