While Bradley obviously couldn’t spill the beans too much about what puts the episode “Twice Upon A Time” on the same level as It’s A Wonderful Life, he did indicate all the pieces are there for it certainly to be an iconic episode in the show’s history.
Previous to his appearance in “The Doctor Falls,” David Bradley had portrayed the Doctor before, but it was in a docudrama in which he played the actual actor of the First Doctor (William Hartnell).
Bradley may be a bit biased to judge how good the Doctor Who Christmas special is though, as he tells Comicbook.com he was thrilled to be joining the cast to play the First Doctor.