After two long years, our international 'Sherlock' nightmare has finally come to an end, as the great detective has officially returned with at least one apparent explanation for his monumental "Reichenbach Fall." And while the explanation may only satisfy some, the game will go on with our first trailer for follow-up episode "The Sign of Three!"

You're warned of major spoilers from here on out, particularly for us poor Yankees waiting until the January 19 U.S. airing on PBS, but after revealing the mystery of "The Empty Hearse," Sherlock Holmes (Benedict Cumberbatch) will face his biggest challenge yet during January 5 U.K. follow-up "The Sign of Three": acting as John (Martin Freeman)'s best man! The first full trailer for the installment has arrived, and suffice to say, 'Sherlock' wouldn't be 'Sherlock' without a dash of murder to the big day (don't forget our Comic-Con 2013 report on the footage!).

Elsewhere, series creators, writers and star Steven Moffat and Mark Gatiss opened up in a new video interview to describe how they arrived at the conception of, and an explanation for Sherlock's mysterious survival, which had to adhere to strict settings of plausibility. John ended the season 3 premiere still lacking an official explanation, but should we take Sherlock's earlier confession at his word? Is Moriarty really dead, after another fan theory posited that the two were in sexy cahoots the whole time?

Check out the first trailer for 'Sherlock' season 3's second installment "The Sign of Three" above, and watch Moffat's interview below before giving us your own survival theories in the comments!

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