What to expect from the upcoming special of "Sherlock" is revealed. Co-creator Steven Moffat opens up that the show which started as a modern day re-interpretation of Sherlock Holmes will return to the original time period in Victorian London for the special, AceShowbiz reports.

"The special is its own thing," he teased to EW. "We wouldn't have done the story we're doing, and the way we're doing it, if we didn't have this special. It's not part of the run of three episodes. So we had this to do it - as we could hardly conceal - it's Victorian."

"[Co-creator Mark Gatiss] and me, we wanted to do this, but it had to be a special, it had to be separate entity on its own. It's kind of in its own little bubble," he added.

No release date has been announced, but the 90-minute episode is finished. It's excepted to broadcast around December in U.K. Benedict Cumberbatch and Martin Freeman were recently spotted wearing vintage outfits during a filming.