A devastating existential nightmare. You know, for kids!

Oh noes, Clara's going to destroy all the existing TARDIS keys with lava, such peril! How will the Doctor ever get back into his TARDIS now, other than by snapping his fingers, which he's been able to do for the last three regenerations?

"Dark Water"/"Death in Heaven" by Steven Moffat, directed by Rachel Talalay. Spoilers after the cut.

That would be Rachel Talalay who started her directing career with one of the Nightmare on Elm Street sequels, so it seems fair enough she's now directing a Doctor Who finale so bleak it's taken me weeks to say anything about it. Although I always seem to end up forgetting to do a post about the finale for a couple of months, and now I don't know what to say about it.

I did love Michelle Gomez's evil Mary Poppins take on the Master/Mistress though, and the Missy revelation for the cliffhanger was very well done. I also liked the little farewell to the Brig, with him being above letting such little things like turning into a cyberman affect his personality. It's all a bit "You can't mesmerize me, I'm British!" which is never a bad thing, and very Brig.

It could have been a cheesy ending but to be honest it was kinda needed after a super-dark couple of episodes, that for me went that little bit too far - specifically, the idea that the dead continue to feel everything that happens to their bodies, including their own cremation or decomposition. That's the kind of existential nightmare a horror film would consider a bit much, let alone a family show. I think that particular plot point was kind of quietly said not to be true in Part 2, but the idea's out there now. I like that Capaldi's era has followed through on going for a darker side, but I do think the season finale could have remembered to be a bit more fun along the way.