A merry little Christmas: Katherine Jenkins, left, guest stars in the Doctor Who Christmas special alongside Michael Gambon, centre, and Matt Smith, rightIt's become as much a part of the celebrations as pudding, opening presents and the Queen's Speech - and now the cast of this year's Doctor Who Christmas special have revealed a sneak peak of just how festive it gets behind the scenes.
The Doctor himself Matt Smith, 28, plus Karen Gillan, 23, who plays sidekick Amy Pond, belt out Have Yourself A Merry Little Christmas accompanied by Arthur Darvill, 28, who plays Amy's husband Rory Williams, on piano.
The bit of backstage silliness will be screened on BBC3's Doctor Who Confidential, on at 7pm after the main event on BBC1 - and proves that red-headed Amy has a quite an impressive set of lungs, even if she doesn't manage to quite hit the high notes.
On song: Doctor Who's Karen Gillan, Matt Smith and Arthur Darvill (on the piano bottom right) belt out their rendition of Have Yourself A Merry Little Christmas in a sneak peak of this weekend's Doctor Who Confidential on BBC ThreeIn fact, the trio pretty much murder the festive favourite, made famous by Judy Garland in the musical Meet Me In St Louis - but it's all part of the fun of the Christmas Confidential special.
As well as the seasonal singsong, it's set to show all the behind-the-scenes merriment of a good old-fashioned Doctor Who Christmas, which makers are promising will be extra-special this year.
Called Doctor Who: A Christmas Carol, it's based around the Charles Dickens classic and guest stars 20-year-old opera diva Katherine Jenkins as Abigail Pettigrew and Harry Potter star Michael Gambon, 70, as Kazran.
Seasonal scenes: The Doctor Who special is based on Charles Dickens' A Christmas CarolKatherine has said of the
In Doctor Who Confidential, Matt and the cast are to show fans around the show's Cardiff sets and go backstage with the stars of the Dickensian Christmas special.
Michael Gambon meanwhile will also talk about swapping his wizard's wand for a taste of the Doctor's time-travelling magic, Katherine Jenkins waxes lyrical about her acting debut, plus there are interviews with show writer Steven Moffat.
Special guests: Katherine Jenkins joins the cast as Abigail Pettigrew, joined by Michael Gambon as KazranKatherine has said of the show: 'This Christmas special is the most Christmassy Doctor Who that they've ever had.
'It has all the brilliant scientific and all the excting parts of DW that it normally has, but there is also running through it a quite emotional heartbreaking story and it's very closely linked to a Christmas Carol.
'People will be moved and relate to it. We've not set out to make people cry over their Christmas dinner, but it's heartwarming.'
'The Doctor is going pretty wild on Christmas day 'cos he's excited. As a Christmas treat, it would be pretty high on my list!'
Though he added darkly: 'There is a shark involved though, yes.'
Doctor Who: A Christmas Carol, BBC One, 6pm, Christmas Day
Doctor Who Confidential Christmas Special, BBCThree, 7pm, Christmas Day
Doctor Who cast sing a Christmas carol - Doctor Who Confidential - BBC Three
Doctor Who: A Christmas Carol - Christmas Special 2010 trailer - BBC One
source: dailymail