Sherlock returns to the BBC on New Year’s Day and to PBS on January 19 for three new 90-minute installments of the detective drama. As a pre-holiday treat, the BBC has posted a seven-minute mini-episode that provides some exposition for the new go-round. (The move is similar to the BBC’s tease of the 50th anniversary Doctor Who movie Day Of The Doctor last month.) The network also offers a new blog post by Dr John Watson promising it will be his last, as it’s time for him to “move on” (read it here). Watson (Martin Freeman) and Detective Inspector Greg Lestrade (Rupert Graves) feature in the mini-ep, titled “Many Happy Returns”, as does Benedict Cumberbatch‘s titular high-functioning sociopath — with a wink. Check it out:

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