Sherlock creator Steven Moffat has revealed the three key themes of Series Three will be
RAT
WEDDING
BOW
Can you guess what the three words stand for?
Speaking to a room of TV industry insiders and journalists at the Media Guardian Edinburgh International Television Festival, Moffat, joined by Sherlock producer (and his wife) Sue Vertue, co-creator Mark Gatiss and actor Andrew Scott, also spoke about how the BBC show became an international success story.
Moffat said: "We love Sherlock Holmes so much - this is fan fiction! We wouldn't have minded if nobody had watched it and we'd have been able to keep making it for each other."
Gatiss had previously hinted that the first episode of the next series will be an adaptation of Conan Doyle's story The Secret Of The Empty House.
The first mystery that needs explaining is how Sherlock cheated death to appear at his own graveside, after he was seen jumping from the roof of a high-rise building.
During the masterclass, Moffat and Gatiss both claimed that they know how series two's cliffhanger will be resolved.
Earlier in the day, while on his way to the Festival, Moffat played a hoax on fans when he tweeted his followers: "I'm revealing the three words for S3 early. Pipe, slippers, bed. There you go."
Gatiss and Moffat previously revealed clues to the second series in similar fashion with the words 'woman', 'hound' and 'fall'.
Those ultimately referred to Sherlock's femme fatale Irene Adler, the Hound Of The Baskervilles, and the concluding episode which ended with Sherlock's fall.
Andrew Scott, who plays Sherlock's enemy Moriarty, was also at the masterclass. He told the audience he was "absolutely terrified" about messing up his part, after noting the early affection for Sherlock from the UK public.
He revealed he looked at Twitter to see what people thought of his performance and compared the experience to being "kissed... then punched... then hugged..."
Scott refused to confirm if he'll return as Moriarty in a third series, reminding the audience, "Moriarty is dead."
Filming of Sherlock series three is due to commence in early 2013 and the show is set to return to TV in the autumn.
While on a break from Sherlock, Cumberbatch has starred in Parade's End which starts tonight at 9pm, BBC2. Here are lots of beautiful pictures to get you in the mood...