This year’s Doctor Who Christmas special will have twice the Time Lords and departures: Both Peter Capaldi and Pearl Mackie are exiting the series. But let’s not think of that as we watch the latest teaser for “Twice Upon A Time.”

Instead, let’s marvel at David Bradley, who’s filling in for William Hartnell as the first Doctor, and is therefore not taking any of the Twelfth Doctor’s guff about being The Doctor. Neither is he impressed by the sonic sunglasses (he’s not alone there), which have made their return yet again. The clip doesn’t give us much more background on what the latest set of impossible odds the Doctor (both of them) will face are, but it does have a great Capaldi voiceover and a glimpse at the regeneration. We also see Bill (Mackie) for one of the last times. Don’t worry, though—new Who showrunner Chris Chibnall has recruited a whole batch of companions.

“Twice Upon A Time” comes to BBC America December 25.