With exactly one month to go until the Doctor's tenth (can you Adam and Eve it?!) annual festive adventure, the BBC has set tongues wagging today by revealing its intriguing title, and we've even been treated to a sparkling new poster image - above - too! We now know that the Twelfth Doctor and Clara Oswald will return to our screens in Last Christmas, written by Steven Moffat and directed by Paul Wilmshurst, which is set to air in the show's traditional Christmas Day time slot as the centrepiece of BBC One's yuletide festivities. Confirmed guest stars for the special include Shaun of the Dead and Hot Fuzz's very own Nick Frost, who was introduced in the closing credits of the Series 8 finale, Death in Heaven, as Father Christmas (no, seriously), as well as Dan Starkey and Nathan McMullen, who will seemingly be playing two of Santa's devoted elves, Ian and Wolf. You couldn't write this stuff, could you? Until now, all we've had is the teaser trailer and a Children in Need preview clip to help us wile away the remaining weeks, but the episode's title has already caused quite the stir amongst fans, with the latest development becoming the subject of fevered speculation across social media and the Doctor Who blogs, and not just because of its uncanny resemblance to a popular 1984 Christmas song written by George Michael. As with most Steven Moffat episode titles, there are a number of reasonable - and some not so much - explanations. Here are five of them, or, rather, five things the title of this year's Christmas Special could, but probably won't, but inevitably most likely will, mean...