London, 1893: It's dark and dank and prison-y. A crazy man mutters about the "Whispermen." A noise! A lizard! It's Vastra (so happy to see her again) and the bald crazy man wants to make a trade. He's been tuning into "the babble of the world" and has information about something in exchange for his life -- and not just any information: This bit is good enough to save him from his crimes as a woman-murderer. The Doctor has a secret that he will take to his grave. "And it is discovered."
That's good enough for Vastra, who arranges "a conference call" with her good (human) wife Jenny, gathering the gang. Strax -- it's his weekend off -- is in Glasgow fighting (apparently to death) and has to be knocked out by his opponent after a street urchin interrupts their battle with the message. Clara is back at home with the kids, making a soufflé. There's chatter about the metaphysics of soufflé-ing. She notices a letter. It's old! It's more: Reading it, Clara learns that Vastra has enclosed a candle which contains a soporific which will induce a trance that will carry her across time and space so that they might convene. It's important. It's about the Doctor. But Vastra, assuming that Clara might not trust her or the strange correspondence, has doused the letter in the same substance. Out Clara passes.
The trance looks like this: There are candles, classical music, and a fancy inscribed table around which we find Vastra, Jenny, Strax, and now Clara. The tea is quite good (it's made of memories). Clara's surprised to be there, but she's more surprised to learn of the imminent arrival of one River Song. River Song? River Song! And there she is, the professor, topped with hair and (disgracefully) summoning a bottle of champagne at her elbow. Clara's heard a lot about her, of course, but she never knew that Professor Song was a woman. River doesn't seem to have known anything about the Doctor's newest "current traveling assistant." This will change.
With a swirl, Vastra calls up some dust-y particles to replay footage from that earlier prison scene, with the crazy man spilling his spoils. He has space-time coordinates, the location of the Doctor's greatest secret -- which no one knows, because no one knows the Doctor's greatest secret. Clara thinks she knows it, probably. Well then: What is the Doctor's name? Clara doesn't know and can't remember why she doesn't know. River knows, but obviously. (How? "It took a while," she says.) Clara's confused -- so many new faces! River is a friend of the Doctor's; indeed, she is...a little more than (a long time ago, of course; everything major in the Who-verse happens a long time ago, meaning now). But the Doctor hasn't contacted River in quite a long time. Vastra disapproves, but the professor shrugs. "He doesn't like endings."
Anyway, River wants to know how they know that the prisoner was telling the truth. Vastra says he gave her one word: Trenzalore. That makes things worse, actually. How did he describe the information, exactly? Re: the magic dust video. River says they've misunderstood, with graveness on the syllable mis.
At the same time, Jenny has been freaking out because she thinks that she forgot to lock the door before she and Vastra went into the trance and she thinks that someone has broken in and (not now, Jenny!) she thinks that she might have been murdered. With a single tear, Jenny disappears, dead. It gets worse: White-skinned, black-mouthed creatures in top hats are attacking each of them in turn. "Tell the Doctor," they chant. "His friends are lost forevermore unless he goes to Trenzalore."
NEXT: To Trenzalore