Both fiction and philosophy have been exploring the notion that we could be living a dream and not realize it ever since, well, probably about five minutes after the first person woke up from the first dream. It’s the stuff of late-night forays into unanswerable questions, and it’s served as the root of countless plot twists both before and after Bobby Ewing stepped out of the shower in Dallas. “Last Christmas” doesn’t so much attempt to reinvent the wheel as to bolt it to a unicycle and invite us all along for a ride. It takes the concept of multiple nested dream states and just goes nuts with it, ensuring that anyone playing a “take a shot when it’s a dream” drinking game will wind up in a coma before the end credits.
But what keeps the Russian doll narrative from getting tiresome is that Steven Moffat’s script is constantly showing its hand and daring you to notice. Moffat quite cleverly uses our own experience as TV watchers against us, disguising the story’s twists behind well-worn storytelling tropes like having characters defuse something obvious by commenting on it (“They’re a bit like facehuggers, aren’t they?”), brushing aside unnecessary details (“It’s a long story.”), or climactic act breaks that are easily resolved after the commercials. As plot twist follows plot twist, one of the episode’s most satisfying elements is realizing how many of the clichés have been weaponized and used against us. (How long did it take you to notice that the number of dreamcrabbed people in the infirmary matched the number of researchers still standing?)
7) Clara Always Looks the Same to The Doctor
It’s anybody’s guess what it would really be like to be a functional immortal whose head is attempting to store a thousand years’ worth of memories, but Doctor Who has had gotten a lot of mileage over the years in imagining what that might do to your perspective of life, the universe, and everything. “Last Christmas” adds a lovely little touch by suggesting that The Doctor can’t tell the difference between an aged Clara and the “current” version. After all, what are a few decades of decrepitude to an alien who skips between centuries like we walk between rooms?