Ever-increasing as demand for Benedict Cumberbatch and Martin Freeman becomes, ‘Sherlock‘ fans well-know that the gap between series can be murder. And though we’ll have Sherlock and Watson returning for a BBC special one-off sometime in 2015 before production begins on season, our first look at the Baker Street boys back in action has already arrived in a gloriously mustachioed photo!

As teased through the BBC Twitter account, our early sneak peek of the 90-minute one-off ‘Sherlock’ special sees both Benedict Cumberbatch and Martin Freeman sporting surprising new looks for their characters, or familiar ones, depending on the context. John Watson’s glorious mustache returns, while Sherlock seems to have traded in his deerstalker for something a bit more formal, so what are we looking at?

Someone’s fantasy? Fan-fiction? A dream? Or perhaps, might the long-desired ‘Doctor Who‘ crossover finally come to fruition, sending ‘Sherlock’ back in time to Sir Arthur Conan Doyle’s London?

When last we heard, showrunner Steven Moffat had plotted through a potential fifth season of the series, while the fourth was projected to air sometime in 2016. Along with the surprise resurrection of season 3 finale “His Last Vow,” Moffat also specified that ‘Sherlock’ season 4 would likely see increased roles for the women of the series, particularly Molly Hooper (Louise Brealey) and Mrs. Hudson (Una Stubbs), potentially adding new female characters into the mix as well, as part of “Sherlock’s gradual humanization.”

Production won’t formally begin until January, but feast your eyes on the glory of John’s mustache (and sure, Benedict Cumberbatch, why not) in our first photo from new 2015 ‘Sherlock’ below, and give us your theories on the old-timey look in the comments!

Sherlock Season 4 2015 Special Photo Mustache

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