UPDATE with more detail: Filming has begun in the UK on the much anticipated Season 4 of the BBC One/Masterpiece drama Sherlock. Three new episodes are afoot promising “laughter, tears, shocks, surprises and extraordinary cases,” the networks said today. Benedict Cumberbatch returns as the high-functioning sociopath alongside Martin Freeman as Dr. John Watson and Amanda Abbington as his wife Mary. The latter two will be preparing for the arrival of their first child.

Ghosts are also said to figure heavily in the new season (Moriarty?) while co-creators Steven Moffat and Mark Gatiss appeared to have teased this could be the final go-round for the group, saying, “This is the story we’ve been telling from the beginning. A story about to reach its climax.” However, the typically cryptic duo has also previously said they see the series continuing for a long while and I’m told the word “climax” could mean anything, but not the end. There’s currently no airdate, but speculation is that a January 1, 2017 return may be in the offing.

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Produced by Hartswood Films, the series made a triumphant return to television on New Year’s Day this year with a special episode that scored 8.4M overnight viewers on BBC One. It was the most watched program over the holiday season with 11.6M consolidated viewers and the highest ever audience share for the series. The 90-minute installment, The Abominable Bride, was then released theatrically and notched big box office, notably in China and Korea.

The three-part Season 4 will begin with an episode helmed by Rachel Talalay (Doctor Who, The Flash).

Cumberbatch said he’s “genuinely thrilled to be back filming Sherlock with all the cast and crew. I can’t wait for everyone to see season four. But you will have to wait… though not for long. … And it will be worth it.”

Co-creators, writers and executive producers Moffat and Gatiss added, “Sherlock series four — here we go again! Whatever else we do, wherever we all go, all roads lead back to Baker Street — and it always feels like coming home. Ghosts of the past are rising in the lives of Sherlock Holmes and John Watson bringing adventure, romance and terror in their wake.”