So we start off with a creepy kid and a creepier snowman. That talks. And parrots back the kid's statement that they other children are silly and to be ignored. Right, not to worry then. Suddenly we zoom forward 50 years. Creepy kid is now a creepier adult who feeds people to snowmen. The Doctor is being down right grumpy to Madam Vastra, Jenny and (somehow alive, they explain it but not really, just go with it, it's Doctor Who) Commander Strax. He meets a nice barmaid (Clara) who looks exactly like that girl from Asylum of the Daleks (except he never saw her then). They also meet a creeptastic snowman. The Doctor stops the snowman and wanders away to a carriage which Strax is driving. Clara then breaks into the carriage.The Doctor decides to wipe her memory with a special worm (coughforeshadowingcouch). Strax keeps forgetting to use gloves and thus keeps getting wiped. His forgetting that he climbed under the carriage and the subsequent belief that he was run over was great. Anyway, Clara manages to convince the Doctor that he can't wipe her memory, or she'll forget how to fight the snowmen. The Doctor then saunters off and climbs into the cloud that the TARDIS is parked on. Clara is somehow able to follow him without his noticing, but she doesn't go in the TARDIS.
The Doctor sits in his newly redecorated TARDIS (though the outside could use a fresh coat of paint). He is sad. Clara goes to her other job as a governess where she uses a fake posh voice and entertains the children by using her real *secret* voice. We learn that the former nanny, a real meany died a year ago by drowning in a pond that then froze over. *Shockingly* the girl is having nightmares about this.
Clara tries to get the Doctor, but is too short to reach the ladder. Luckily Jenny gets her and brings her to her wife, Madam Vastra (yay, they confirmed it!). Vastra asks her lots of questions and lets her only answer with one word each. Clara says pond and gets the Doctor to actually come and help. The Doctor, dressed as Sherlock Homes (Wholock!), who the creepy guy (real name: Dr. Simeon) claims to be based off Madam Vastra/Jenny, visits the creepy guy. He makes lots of really funny, but really inaccurate deductions, before narrowing in on the snow, or Great Intelligence. He also throws a folder on the ground and figures out that they want to use the pond that the governess drowned in because her DNA will help them build new snow creatures.
The Doctor shows up at the house where Clara works and saves her and the children from the governess who has risen anew entirely made of ice. There's a sweet moment where he realizes he's wearing a bowtie, but utterly fails to realize that it's the temperature that's cool, not his bowtie. Aside, Strax mentioning that he brought grenades was great. Anyway, ice lady is still attacking, Jenny and Vastra show up to help. Ice lady gets trapped in the house and new snowmen show up to try and get her. The Doctor grabs Clara and gives her an umbrella. They run to the roof, chased by the ice governess. Clara decides the the umbrella was given to her because she is short, it's her only way to reach the sky ladder (the Doctor doesn't control the cloud to move it, merely the wind). They race into the TARDIS which she declares to be...smaller on the outside. "That's new." Also new? Her desire to make souffles in the TARDIS kitchen. Alas, just as Clara gets a key to the TARDIS she's yanked outside by the ice lady who throws them both off the
I'm interested to see where this story with Clara ends up going. I have a feeling that my favorite theory that I've seen will prove to be incorrect (She's the daughter of Jack and a weeping angel. Every time she dies she gets sent somewhere new in space and time).
Also, new opening titles. I liked them.