Posting this behind a massive Spoiler warning because it’s a pretty big reveal, though not a completely unexpected one if you’ve read any of my other spoiler posts, or noted that the opening scene in World Enough and Time bears a striking resemblance to one of the last scenes of another famous Doctor Who episode.
Yep, that’s David Bradley playing the First Doctor during the Christmas Special. I’ve been hearing rumors for months, and for a long time expected that it would be him hiding in the vault instead of Missy. While I have mixed feelings about recasting past Doctors, I’ll give Bradley a pass because he looks way more like Hartnell than Richard Hurndall ever did.
Given that World Enough and Time begins with the Doctor stepping out into a blizzard, trying to hold back his regeneration, I’m assuming that’s the same blizzard the First Doctor wanders through at the end of The Tenth Planet, and that The Doctor Falls ends with the First Doctor wandering into the wrong TARDIS.