When 'Doctor Who' Met 'Sherlock'

Did you hear that sound over the weekend? That was the sound of a million fans of both "Sherlock" and "Doctor Who" simultaneously going "Squeeeee!" over this fan-made trailer for "WHOLOCK" — a fanciful meeting of two British cultural icons.

In it, Sherlock (Benedict Cumberbatch) hears a noise outside his flat at 221B Baker Street and looks out his window to see the TARDIS has landed. He steps out onto the street and spies the Doctor (Matt Smith) peeking out of the contraption, then follows him inside. Once inside, Sherlock marvels at the machinery and (of course) wants an explanation. The Doctor invites him on a time-tripping adventure, and after some initial skepticism from Sherlock, the two hurtle through time and space together to ... God knows where.

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The five-minute video doesn't simply splice together close-ups from each show to make it seem like the two are together. As the video below demonstrates, "John Smith" (the only information the visual-effects whiz offers about him or herself) used After Effects, Photoshop, and Premiere to put the Doctor and the detective in frame together for the first time.

It's no surprise that so many fans of one show would also be fans of the other. Of course, both shows are produced by the BBC, and both have long histories; the Doctor just turned 50, and Holmes is still looking sprightly at 126.

Plus, both shows are also currently being run by the same man: Steven Moffat, who took over "Who" in 2010 and co-created the latest iteration of "Sherlock" the same year with Mark Gatiss (who also plays Holmes' brother, Mycroft, on the series).

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Of course, the unanswered question: Is Sherlock the Doctor's companion? Or is the Doctor Sherlock's Watson? Only Moffat would know for sure.

The “Doctor Who” Christmas special airs Dec. 25 at 9 p.m. on BBC America. Season 3 of “Sherlock” premieres Jan. 19 at 10 p.m. on PBS.