Steven Moffat, the creator of BBC drama Sherlock, has set tongues wagging after discussing details of the forthcoming fourth season of the show. Steven Moffat and fellow creator Mark Gatiss were quizzed about the return of the acclaimed detective series at the Emmys on Monday (August 25, 2014).

SherlockBenedict Cumberbatch [L] and Martin Freeman [R] in 'Sherlock'

"We have a plan to top (season three)," said Moffat. "I do think our plan is devastating. We've practically reduced our cast to tears telling them the plan.we're probably more excited than we've ever been about Sherlock."

'Sherlock' stars Benedict Cumberbatch and Martin Freeman won two awards at the Emmys, with Moffat winning outstanding writing gong for his work on the season three episode 'His Last Vow'.

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Speaking at the HBO after-party, Gatiss dropped further hints and promised that he and Moffat would take the show "somewhere we've never been before - and I don't mean outer space".

Sherlock castSherlock is on the way back

"It will be a challenging place to go," he told Entertainment Weekly. "We always start with a re-introduction that builds toward a darker climax - we might just be going darker. We've got a very, very good set of ideas."

Season four of Sherlock is likely to reach screens late next year with a one-off special an a new three-part series. 

A flurry of tweets posted on the official Sherlock Twitter feed in July told fans that "after the briefest of exiles, Sherlock will return to face one of his biggest mysteries yet". Exact airing details are yet to be confirmed though Moffat insisted that "when they go out is up to the BBC," adding, "I am their loyal servant, I simply do what they ask me."

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