Woman: You all right? The Doctor: A pram? At midnight? [Climbs out of the head through the eyehole] Really? Woman:[Angrily flips the hood down, revealing full grocery bags instead of a baby] It's my shopping. [The Doctor boggles in disbelief.]
In the "Ruby meets the Doctor" clip we see Ruby hanging on a ladder from the goblin ship when the Doctor appears and then proceeds to sass her up:
The Doctor: What the hell are you doing?! Ruby: I'm... just... there's—! The Doctor: But what did you do that for?! Who sees a ladder and just pops on?! A ladder in the sky, and you thought "Yeah, I'll give that a go, babes!" Ruby: THEY'VE GOT THE BABY!
It's worth pointing out that the Doctor is saying that while jumping over the rooftops while chasing the very same ladder. And then jumps on said ladder.
Everyone thinks that Lulubelle is a terrible name except the Doctor, who idly wishes he was named "Lulubelle".
Ruby accuses the Doctor of being an expert in time travelling Goblins. He seems to take enormous offence at the fact she called them time travelling goblins, complaining that they "just bimble" while actual time travellers (namely him) are "great. Like, the best. Like, wow". He may be more mellow, but, no, the ego is still there.
...and then the Doctor and Ruby land in front of the King, literally Letting the Air out of the Band. The Doctor’s plan? Restart the music, even improvising new lyrics.
The Doctor: Rock it, Janis! [band starts playing again]
After Ruby and the Doctor make it back to the flat with Lulubelle, Carla returns from her trip to the supermarket and asks what's going on, to which the Doctor and Ruby immediately begin Acting Unnatural with big grins and awkward posing to avoid having to explain the entire adventure they've just been through. And right after Carla accepts their flimsy excuses with Ruby introducing the Doctor to her, Ruby and the Doctor proceed to argue in frantic whispers over throwing each other under the bus during the explanations.
The Black Comedy of Davina McCall showing up as a celebrity Special Guest only to be subjected to the goblins' cruel tricks and getting killed by a Christmas tree (she gets better thanks to the Doctor’s meddling).
The scene in which Davina calls Ruby before The Reveal of her in a wheelchair and several casts is definitely worth a morbid laugh given how it goes from a sad and heartfelt moment of Davina breaking the news to Ruby before zooming out to her injured state.
Not to mention the list of accidents that led to the injuries.
Davina McCall: I've been hit, I've been thrown, I've been bumped, I fell off a boat on dry land. I've been in accidents, collisions, I've even been trampled by a moose!
Her near-fate might also remind some of the early Christmas specials of RTD's first run in which killerChristmas trees were a bit of a thing.
Jackie Tyler: I'm gonna get killed by a Christmas tree!
The fact the audience thinks RTD turned Davina into a Dead Star Walking until the very end, when the Doctor narrowly averts Something We Forgot at the very last moment.
The Running Gag with Ruby's gran Cherry griping about not being able to get a cup of tea. At one point, after Ruby and the Doctor have returned from their baby-saving escapades, Cherry snarks that she's given up all hope of getting that tea and accepted a life of abstinence.
The Nan-E filter censors swearing using Gosh Dang It to Heck!, and the euphemisms make it very clear what the original words were, to hilarious effect.
The slowly dawning horror as Ruby discovers the spaceship dripped baby snot - from which the Bogeyman is made - all over her head. The Doctor can't help but laugh at her misfortune.
Ruby: This is the worst thing that has ever happened to anyone!note Oh, Ruby. If onlyyou knew how wrong you were.
The Stylistic Suck of the alternate EMI/Abbey Road Studios, where all the music has been stolen by Maestro. The Beatles sing about a dog, Cilla Black sings a generic love song, and an orchestra plays a horrifically dissonant rendition of "Three Blind Mice".
Paul McCartney: "I've got a dog, he's called Fred.
My dog is alive, he's not dead.
I love my dog, he loves me too.
I haven't got a cat, only a dog."
Cilla Black: "I love you, you love me.
We are two, we are not three.
'Cause you love me and I love you.
We're quite happy, I think, perhaps."
The slow creeping Flat "What" faces on The Doctor and Ruby as they realize how bad the songs are. By the time they hear the orchestra playing "Three Blind Mice", The Doctor is hunched over and close to hyper-ventilating.
Just because The Doctor is standing on a planet-destroying landmine doesn't mean he'll pass on any opportunity to snark on Villengard's inhumane business practises.
Ruby: Why does a land mine have lights on it? The Doctor: Oh... capitalism. Flashy lights play well in a showroom. Modern warfare - death by salesman. a little later on The Doctor: It's vacuum drones, that's all. Hoovering up the smoke, so that nobody can choke to death before they are safely shot.
Ruby's Gallows Humor at The Doctor's expense, when he promises to be cross with her for a long time if they survive the gambit to trick the landmine's sensor.
Ruby: Not that long, babes. You're standing on a land mine.