Overall, this one is perhaps the most absurd/insane/just plain bizarre episode of Who since, possibly, "The Feast of Steven". Which was screened almost fifty years ago.
... Yes, that's definitely the weirdest start I've seen. I wonder how they're going to explain THAT.
Naming the whole show after a Wham song isn't all that promising... but at least the song the one going into the ward is singing is a bit better. Slade, maybe?
... and Santa Claus, again. I think this is now the Strangest Who Episode Ever.
"That's racist. Elf-ist. Which is a bit hypocritical coming from someone of your height..."
"How do you get all the presents in the sleigh?" "Bigger on the inside."
"They're a bit like facehuggers, aren't they?"
"There's a horror movie called Alien? That's really offensive. No wonder everyone keeps invading you."
All right, it's probably going to end up that most - if not all - of the weird shenanigans are going to turn out to be connected with the strange dreams. It's very obvious that this is what the late Danny is doing back, anyway.
"Head toward the Northern Lights. Yes, I remembered to turn them on..."
"You're not real." "That's never stopped me."
"No. No. Line in the sand. Santa Claus does not get to do the scientific explanation."
"There are a lot of dangerous things on this planet, Clara. Most of which, you eat."
"I know all your home addresses."
... Yes, it was fairly hard not to just type the words WHISKY TANGO FOXTROT in place of an actual set of snippets...