While I’m not planning to go into a lot of plot details, it’s likely that the random mutterings that follow will reveal some things you might prefer not to know if you haven’t seen the episode yet, so in my usual way, I’ll include this warning:
OK, so here we are at the midpoint of the series, and things are getting interesting. Knobs are being turned up to 13 (11 is for amateurs) and threats are growing.
This is one of Stephen Moffat’s more devious little numbers, involving flashbacks, misdirection (though with some hints provided, clever that) and all leading to a set-up for what’s coming next.
But enough metatalk and on with the story. We start with a flashback to a long time ago (amount of time carefully not stated for reasons of plot, I suspect, but if it turns out to be 999.999 years in the past, I wouldn’t be even slightly surprised at this point), on a planet whose people have a reputation for finding ways of killing every kind of life – even Time Lords, who are notoriously difficult to actually kill. And they’ve got the Doctor. After describing the inventive method they’ve devised, and explaining that for reasons of wibble the act must be carried out by another Time Lord, they bring out Missy. And after the customary period of confusion, it appears that it’s Missy rather than the Doctor who’s due for execution. After a brief interruption from Nardole in the guise of a spiritual adviser, but actually bring a message from the late River Song concerning his licence to kick the Doctor’s arse, the Doctor totally fails to kill Missy, scares off the odd people and gets Nardole to help him put her in the vault, which he has sworn to guard for a thousand years. All of this fun is revealed in sections throughout the episode, of course. Couldn’t have a single narrative to keep it non-confusing, could we? But at least we now know for sure who’s in the Vault.
Back in the present, the optically-deficient Doctor is sitting in front of the Vault when he gets an incoming email on his sonic shades – yes!!! they’re back, only this time being useful, giving him a low-res radar image of what’s going on around him.
And that’s where it starts getting interesting. For a start, he’s visited by the Pope and a bunch of Cardinals (that doesn’t happen…), who want him to help them with a mysterious document known as Veritas, which naturally made me think of old BackupExec manuals. Apparently anyone who reads this immediately kills themselves. So maybe it is an old BackupExec manual, those things were heavy going as I recall.
Pausing only to ruin the kind of date Bill doesn’t generally have, he heads for the Vatican, where things get even stranger. There’s the forbidden library which would give M C Escher and the architect of Hogwarts bad dreams, for a start. And the portals which keep appearing all over the place. When Bill and Nardole enter one of these, they find themselves in the Pentagon, which can’t be a good thing.
They then find themselves at CERN, where a copy of the translation of the Veritas document has been sent, where they learn more non-optimal things.
And then Nardole works out what’s happening.
Naah, not going to tell you the rest. Hints were given about what’s really been going on, and soon enough we learn why it’s been going on, and what’s coming next…
Good stuff – nicely twisted and devious, just the way I like it.
 Is that a word? Well it is now…