Benedict Cumberbatch is “irreplaceable” as Sherlock says Mark Gatiss

Gatiss is presumably talking in the main about the prospect of Cumberbatch deciding it was time to hang up his deerstalker to make room for other projects. But the writer does go on to add the extra, rather thorough, point that “If Benedict went under a bus tomorrow, it would be the end of the show”.

Plus we'd all be in mourning, right Mark?

“Benedict and Martin [Freeman] are our stars,” Gatiss told the Daily Mirror while discussing the modernised adventures of Sherlock Holmes and Dr John Watson.

And though fans are eager for more – having so far been restricted to a three-part series every two years – Gatiss says the stars’ busy schedules continue to play a big part in what's possible.

“We do three episodes a year and although people want more that’s all we can do. They are both so famous now it’s increasingly difficult to get them," said Gatiss.

“Sherlock made Benedict a star and I know he is eternally grateful to the show, he wants to do more. Martin is similar too as he is in The Hobbit and he’s doing a new show in Canada with Billy Bob Thornton, a TV version of Fargo” (in fact, Channel 4 has just snapped up the UK rights to this comedy drama).

Gatiss, who as well as writing the show stars as Sherlock's brother Mycroft Holmes, adds, “They are both major stars but they both want to carry on. We just have to try and make the days work, that’s all.”

A fourth series of Sherlock is in its early stages, but with no confirmed air date as yet.

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