Sherlock star Benedict Cumberbatch has hinted the next series of Sherlock could be the last.

A fourth instalment of the hit BBC drama, starring Cumberbatch as the eponymous detective and Martin Freeman as his sidekick Doctor Watson, is expected to air early next year.

Cumberbatch, 40, told the November issue of British GQ magazine it felt like the "end of an era".

While The Imitation Game star said he would "never say never" to reprising the role, he said the series felt "complete".