Steven Moffat has admitted that he has "no idea" when Sherlock will return.
The writer told IGN that fans could be in for another two-year wait before a fourth series of the hit drama debuts.
"If people have to wait two years, they'll have to wait two years," he said. "[It's like asking] when's the next James Bond film?
"It's not that kind of show that turns up all the time. It's just not. But the good news is, that probably means it will turn up sporadically for a very, very long while."
Moffat - who co-created Sherlock with Mark Gatiss - added: "We'll do what we can [to make the show as quickly as possible] but with no sacrifice in quality."
Amanda Abbington recently confirmed that she will return to Sherlock as Mary Watson, but revealed that she is uncertain "in what capacity" the character will reappear.
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