Benedict Cumberbatch has said he’s “thrilled” to be back working on the series that made him a megastar, as filming for the long-awaited season four of ‘Sherlock’ finally gets under way.

Fans of the BBC series have been promised that “ghosts of the past” will visit the new three-part instalment, which will see 39 year old Cumberbatch return as the famous detective alongside Martin Freeman as Dr. Watson. The episodes will be directed by American Rachel Talalay, whose previous credits include The Wind in the Willows and ‘Doctor Who’.

“I can't wait for everyone to see season four,” Cumberbatch said on Wednesday (April 6th). “But you will have to wait… though not for long… and it will be worth it.” No broadcast date has yet been confirmed.

Sherlock'Sherlock' has resumed filming for series 4

11.6 million people tuned in to the recent Christmas special ‘The Abominable Bride’ in 2015, a record for an individual episode. Except for that, it’s been over two years since Holmes and Watson last graced British screens for a full series, after the third season finished in January 2014.

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The show’s creators and writers Mark Gatiss and Steven Moffat said: “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. This is the story we've been telling from the beginning. A story about to reach its climax…”

‘Sherlock’’s executive producer Sue Vertue added her thoughts, saying: “It's taken a while to gather everyone together for series four but I can confidently say I think it will be well worth the wait!”

With both Freeman and Cumberbatch both much sought-after in the States, scheduling the popular BBC programme has become increasingly difficult over the years. Regular cast members Amanda Abbington, Una Stubs, Rupert Graves, Jonathan Aris and Louise Brealey, but no guest stars have been confirmed as yet. However, Andrew Scott’s Moriarty is always loth to turn up…

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