"And now it's time for one last bow like all your other selves. Eleven's hour is over now, the clock is striking Twelve's..."
Clara's little ditty at the start of this new trailer for Doctor Who Christmas special The Time of the Doctor heralds Matt Smith's regeneration into Peter Capaldi.
"If you want my life, come and get it!" shouts the Time Lord as the siege of Trenzalore begins. And then we hear those four words, delivered by a Dalek.
"The Doctor is regenerating!"
Could that be a slight note of panic in its voice...?
Doctor Who: The Time of the Doctor is on BBC1 at 7:30pm on Christmas Day