Since the show’s revival in 2005, the Doctor Who Christmas Day Special has become something of a yearly tradition. Featuring all the whimsy and adventure of the regular series, but with a holiday-themed twist, each Christmas Special has also guest-starred actors such as Michael Gambon (the Harry Potter series), Kylie Minogue, and (this time around) Sir Ian McKellen (The Hobbit: An Unexpected Journey), ScreenRant said.

New Doctor Who episodes will be released in April of 2013, and this year’s Christmas episode, “The Snowmen,” will bridge the gap between eras in the overall Doctor Who series.

Doctor Who is a British science fiction television programme produced by the BBC. The programme depicts the adventures of a Time Lord—a time travelling, humanoid alien known as the Doctor. He explores the universe in his 'TARDIS', a sentient, telepathic time-and-space-travel machine that flies through the time vortex. Its exterior appears as a blue British police box, a common sight in Britain in 1963, when the series first aired. Along with a succession of companions, the Doctor faces a variety of foes while working to save civilisations, help ordinary people, and right wrongs.