Sharp-eyed Doctor Who fans will spot a plug for rival drama Game Of Thrones in the science fiction show's Christmas special.
Show supremo Steven Moffat paid tribute to the bloodthirsty fantasy epic in one of the final scenes of the episode.
Viewers will see a character with a plan for a perfect day's festive viewing which includes the classic Miracle On 34th Street and a "thrones marathon".
Moffat, who is also behind the success of Sherlock, admitted he nearly added a Doctor Who episode to the list but said it would be "too self-reverential".
Speaking at a preview screening in central London, Peter Capaldi said playing the Time Lord had been "a pleasure".
He added: "It's the easiest thing I've ever done in my life.
"People keep saying to me 'Is it weird being recognised?'
"But the thing is, you walk down the street and people say 'Look, there's Doctor Who'.
"They don't say 'There's Peter, that bloke with funny hair', and they smile as if they are happy to see Doctor Who so you get the benefit of all the smiles so that's a lovely and very special experience."
- PAA