The BBC has given ‘Sherlock’ fans a little taster of the series’ upcoming Victorian special, releasing a picture of its two stars Benedict Cumberbatch and Martin Freeman dressed in period costume.

The picture shows Cumberbatch in a pretty severe and smart-looking waistcoat and suit reclining in a leather armchair, while a moustachioed Freeman is leaning against the chair and standing up.

Sherlock Victorian Special imageThe BBC released this image from the forthcoming 'Sherlock' Victorian special

‘Sherlock’ creator Steven Moffat revealed earlier in 2015 that the show’s producers were planning a one-off special set in Victorian times, standing separately from the narrative of the main series. The broadcast date for the special has not yet been confirmed, but it’s rumoured to be around Christmas this year.

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Moffat and producer Sue Vertue are due to be arriving in San Diego for the 2015 Comic-Con to host a ‘Sherlock’ panel, and the BBC has released this stand-alone image to get the online chatter going. Speaking ahead of their appearance, Moffat said that the 90-minute special would be “a different version of the show we're used to.”

“It's like we checked the books and discovered we'd set it in the wrong time period by mistake and it's like we're correcting it,” he said. “We're really proud of it, we think it's a real cracker. But that'll be it until series four.”

The fourth series of the globally popular series is not due to be aired until 2017, so this feature-length special will just have to tide us over until then. Moffat added that he and co-creator Mark Gatiss (who also stars as Sherlock’s older brother Mycroft in the show) have not yet begun work on writing it.

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