Why is the Doctor breaking the 4th wall? Uh, Doctor, most of us probably have time to google the bootstrap paradox right now. Luckily I know this paradox, though more by the name "stable time loop" or "ontological paradox". So is the Doctor saying that him going back in time to the (actually pretty vague) coordinates from the previous ep caused the event that led the ghosts to sending people to these coordinates? Oh, there the Doctor already explains it. Then why should we google it?
Ooh, more guitar-playing Doctor!

OMG, the opening credits are with more guitar now! Tell me that was played by Peter Capaldi!

The Minister of War? Ooh, did we get a hint of what's to come? Nice!

Hee, O'Donnell taking a moment to fangirl about the TARDIS.

After the last episode I've looked up Tivoli and as expected that was the planet Walliams's character in that hotel-containing-people's-fears episode was from.
"If you occupied us, you'd be home by now." Heh.

Ugh, the Doctor dying is a bit overdone. Get genre savvy, Doctor and Clara!

"The chamber will open tonight." Ooh, is it the Chamber of Secrets?

Aw, O'Donnell wasn't killed off permanently, was she? I mean, there's ghost!Doctor and we know he'll live.
Oh god, letting her die to prove his theory sounds like something the Doctor would actually do. Oh, so what ghost!Doctor says is actually a chronological list. I went back and listened to it again and Lunn will be the only survivor (you know, apart from Clara and the Doctor, who'll definitely come back).

Oh, dammit, the cloister bell. What if it warns of impending reapers (I'm still waiting to see those back)? Ha, yeah, it's very Father's Day, they see their time-travelled selves.
OMG, there's Trabant next to the phone box ♥! East Germany, repesent!

Oh, so that's why Lunn whon't be ghostified, because he hasn't seen the coordinates. And as the last one left will he save the others?

OH! I was wondering about the Doctor at the beginning telling us about the stable time loop, but then apparently changing the past - and then I see something go boom at the dam. So that's what the paradox is about: the flooding of the valley has always been caused by the Doctor. Well, so far, so unspectacular. Does that mean he and Bennett will die in the flood? But maybe actually don't and survive in the suspended-animation chamber?

No, okay. Bennett is safe in the TARDIS.

Heh, there is the Doctor, having travelled the slow path in the suspended-animation chamber.

Huh, so ghost!Doctor was just a hologram and the list it said was just bullshit? That's a bit disappointing.

Ugh, what's with the unnecessary shipping? It smacks of sexism and heteronormativity.