A new teaser has arrived for the eagerly awaited "Sherlock" special "The Abominable Bride."

As fans well know by now, the 90-special is set in Victorian London, where Benedict Cumberbatch is deerstalker cap-wearing Sherlock Holmes and Martin Freeman a mustachioed John Watson. Effectively, the characters as they were known in literature and popular culture for more than a century.

How and why they're in Victorian London is still a mystery, but perhaps that's unimportant.

"Sherlock: The Abominable Bride" will air Jan. 1 on PBS and BBC One.