Last night the BBC followed a repeat of the last episode, The Reichenbach Fall, with the 26-second footage, which shows Sherlock Holmes reappearing in his friends' lives after faking his own death.
There are a few surprises coming up for fans in Season 3, including John Watson's (played by Martin Freeman) new moustache.
The end of the last series was a shocker for viewers as Sherlock and his arch-enemy James Moriarty were seen pitting their wits against each other before Moriarty shot himself dead.
Sherlock was then observed by a fearful Watson plummeting from the roof of St Bart's Hospital.
However, the epilogue of that episode showed Sherlock was still very much alive, despite what his friends had been led to believe.
The programme's writers, Steven Moffat and Mark Gatiss, have been teasing fans with hints about the direction of Season 3 for a few months now, and recently admitted the first episode of the new series will be called The Empty Hearse, which is a play on the original Arthur Conan Doyle story The Adventure of the Empty House.
The third series was initially scheduled to air at the end of this year, but had to be pushed back to allow Cumberbatch and Freeman to complete filming for Star Trek and The Hobbit respectively.