Whoa. I’m not as surprised by Matt Smith leaving as much as I am about the timing of the announcement. With only the 50th anniversary episode and the Christmas special to go, there’s not a lot of time left to build to a transition to a new Doctor.
Spoilers ahead, if you haven’t seen the end of the latest season of Doctor Who. Also, if you’re not a nerd, you probably won’t care about the following ponderings….
Given that we’ve seen that John Hurt introduced as The Doctor at the end of the most recent season, there’s got to be some question about where he fits in. He’s pretty much either got to be between Paul McGann’s Eighth Doctor (who we never saw regenerate) and Christopher Eccleston, making him the Ninth Doctor (and pushing back Eccleston and his successors), or he’s got to be after Matt Smith, making him the Twelfth.
Either way, we now have twelve Doctors on the books and, as most Who fans know, Time Lords get twelve regenerations before they ultimately die. (Of course, The Master has sidestepped this rule; perhaps so too can The Doctor.)
If John Hurt is the Ninth (or is somehow some other pre-Smith) Doctor and Matt Smith regenerates into yet another incarnation of The Doctor, that’ll mean he’s used all twelve regenerations, and the series writers are going to have to start answering the question of what’s going to happen at the end of the Thirteenth Doctor’s run sooner than I’d have thought.