Later, Madame Vastra and Jenny confront Simeon in an alley. Vastra is wearing period-appropriate attire, but Jenny has on some kind of leather tights and boots. It's fetching, but odd. Simeon says something about Arthur Conan Doyle basing his Sherlock Holmes stories on Vastra and her "suspiciously intimate" companion. "I resent your implication of impropriety," Vastra says. "We are married." Presumably they are married to each other, but perhaps Simeon doesn't take it that way, because he seems unmoved one way or the other. Then again, he also seems unmoved one way or the other by the revelation that one of these women is a big green lizard, so who knows? Vastra and Jenny are suspicious of Simeon's very secret institute. Vastra is also suspicious of the snowflakes, which she finds to be a bit telepathic. "Almost as if it can detect and respond to the thoughts and memories of those around it," she says. "It could be a terrible weapon in the wrong hands, don't you think?" she asks. It's an accusation, but Simeon is once again unmoved. He forecasts the end of humankind. As he continues on his way, Vastra and Jenny wring their hands because they need the Doctor's help, except he doesn't help anymore.
He can't resist investigating a bit, though, and is currently sifting through some of the snow, wondering who's behind it. Strax the Sontaran pops up to suggest they go on the attack. He was dead the last time we saw him, but here he is in Victorian England, dressed like a carriage driver. The Doctor tries to act like he's not interested in pursuing the mystery further and calls Strax a "psychotic potato dwarf" when he protests. Roast his chestnuts, Strax! Meanwhile, Clara is locked up in the carriage, raising a fuss. "Silence, boy," Strax tells her. He still hasn't found time to take a class on basic human anatomy, apparently. The Doctor tells him to go fetch the alien worm they'll use to erase the last hour of Clara's memory. Of course, Strax ends up accidentally erasing a bit of his own memory. There's a throwaway line about a friend bringing Strax back to life, so that explains that, I guess.
The Doctor finally finds the memory worm himself, explaining that touching it erases an hour, but the worm can erase decades if it bites you. That will be sort of important later. In the midst of all this, the Doctor notices that Clara still doesn't seem scared. She's too intrigued by the snowman to be scared. The moment she starts thinking about the snowman, it pops up in front of her. It also brings along several of its friends. "They're mirroring you," the Doctor says and implores her to picture them melting. She does so, and she and the Doctor get splashed with the result. Wouldn't this mean they're now covered with telepathic water? They don't seem too worried. The Doctor decides not to worm Clara, because she'll need to remember how to dispatch the snowmen in the future. He sends her off in the carriage with Strax, with stern instructions to forget all about him.