WHAT.
...
NO, SRSLY, WHAT.
Some completely disjointed reaction thoughts:
That kept me 100% fascinated all the way through, unlike the previous three specials, so: win.
John Simm looked like he had the time of his life filming that. Also win.
Ten's little emotional breakdown in the cafe with Wilf made me cry. Understated and oh, pitch-perfect. Oh, Doctor.
TIME LORDS RETURN. WHAT. I figured that was coming as soon as they said "it mends whole planets!" Because, well, clearly. But if this winds up as a massive undo button for everything that's happened to Nine & Ten, I will seriously lose my shit.
Re: "immortality machine" -- oh, Abigail, honey, this was not going to work out well for you even if it had worked. You and Jack should have a nice long chitchat about the realities of immortality, and why that was never, every going to be a good idea. (Also, for some reason, I somehow wanted Jack to randomly walk out of the machine when it got turned on. I don't know why.)
DONNA. DONNA DONNA DONNA DONNA!
The line about how they scavenged the thing from the fall of Torchwood kind of broke my heart a little.
They really aren't going to touch the ramifications of "Children of Earth" on Who, are they? That kind of annoys me. Part of what I love about the Whoniverse is that everything is connected. "Journey's End" was narrative porn for me in that sense. Torchwood, as a program, does a FANTASTIC job of keeping itself in touch with events of Doctor Who; I haven't watched SJA, so I can't judge there, but from what I've heard, it's also A+++ in that area. But when you have something so massively game-changing for one set of characters that doesn't have ANY ramifications in the broader universe, I get tetchy. I understand the logic of this from a marketing/production perspective, but I'm all about the storytelling, and narratively, it really, really irks me. Honestly, if I have my druthers, Jack won't appear in the next part at all (apart from flashbacks; I suspect there will be a crapload of flashbacks to previous episodes in the finale). Because having Jack onscreen without addressing CoE would just...no. His character has been irrevocably altered, and having him back in Who as per his usual would be fairly horrific at this point.
BUT ANYWAY, tangents about Torchwood aside, that was a really interesting episode, and I am all a-flail to see what comes next. Even knowing that it will break my heart.