AceShowbiz -

Sherlock Holmes (Benedict Cumberbatch) and John Watson (Martin Freeman) go back to 19th century London in a new trailer for "Sherlock" Victorian special. The video boasts gothic feels as it sees the titular character going into a dimly-lit place to solve a mystery with his partner. There are also scenes of a woman running on a dark street.

Horse-drawn carriages and pipes replace all the modern stuff fans used to see on the series, and Watson looks different with new mustache. The video also inserts humor related to Holmes' iconic hat as Watson convinces his friend to wear the hat, "You're Sherlock Holmes, wear the damn hat."

Plot details are still vague, but Holmes talks to Watson about shadow from the past which may or may not have anything to do with the case they're working on.

Executive producer Steven Moffat previously teased, "Ghost stories work better in a Victorian setting. Other than that it's remarkably similar," implying that the special would be spooky.

Moffat also revealed that the two main characters would be different from the ones in modern day. "Sherlock is a little more polished, he operates like a Victorian gentlemen instead of like a posh, rude man," he said, adding, "He's a lot less brattish when he's back then and Doctor Watson is a bit more upright."

The special still not has a premiere date, but it's expected to air around the holidays.