Returning just in time to ease our New Year's hangovers, it seems the BBC isn't keen to give away too much about the show's upcoming fourth season.
Mmm, moody. A very heavily retouched Holmes and Watson sit in grim contemplation at 221b Baker Street, apparently not paying much attention to the fact the room is flooded, and Sherlock's violin is casually floating about like a very expensive life raft.
So I approach Season 4's dark tone with some trepidation, especially after the off-putting Christmas episode past year (which started out with such promise and later went off the rails a little too far).
As to why and how Sherlock survives the day is undisclosed, but fans will be eagerly anticipating in this hilarious plot twist in an otherwise darker and more intense Sherlock in season 4.
The spectre of Moriarty is looming once again, while Watson has new family responsibilities having had a baby with wife Mary. He then finds out the mystery behind the act.
"Sherlock" Season 4 will have three episodes.
The first episode of series four is called The Six Thatchers - this is obviously a nod to Conan-Doyle's Sherlock story The Adventure of the Six Napoleans, where Sherlock and Watson investigate a man who has been shattering plaster busts of Napoleon (we won't spoil why).
"Sherlock" fans recently got treated to a new teaser. It is speculated that this season is going to be the last for Sherlock.
While Sherlock said that Moriarty is definitely dead at the end of the Christmas special, this could be a sign that Moriarty will haunt him long after.
This is how Sherlock deduces and solves many of his cases, which to normal people is baffling enough to solve in a day, but Sherlock can do it in a matter of minutes.
"Sherlock" Season 4 returns on January 1, 2017.