Sherlock fans rejoice: BBC One has announced that the Benedict Cumberbatch-Martin Freeman series is returning for a one-off special in addition to a three-episode fourth season.

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BBC One announced the news on Twitter Wednesday that filming would begin on a one-off Sherlock special in January 2015. They also announced that filming would begin on the three episodes of Season 4 later in 2015. Presumably, this means that fans would probably be getting this content by the end of 2015 and/or early 2016.

"After the briefest of exiles, #Sherlock will return to face one of his biggest mysteries yet... #221back," the Twitter account teased. This thought continued into the next tweet, which read, "...why is Moriarty's face being broadcast on every television in the land?"

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They also teased that the "only thing to expect is the unexpected."

News of Sherlock's return comes after Freeman (who plays Watson) spilled the beans that a Christmas Special was in the works.

"I'm speaking off-message here; if this was New Labour I'd get fired -- I think that might be for next Christmas. A Christmas special. That's what I understand," he told the Telegraph recently.

As Cumberbatch (who plays the titular character) and Freeman's stars rise, it has become difficult for the producers of Sherlock to get everyone together. Cumberbatch has been excelling in villainous roles in such blockbusters as The Hobbit: The Desolation of Smaug and Star Trek Into Darkness, while Freeman is busy as the star of The Hobbit franchise and appearing in such shows as FX's Fargo.

Tags: Sherlock television PBS