Academic Athlete: Beth describes herself as smart in her opening narration, and a couple of paragraphs later, the narrative calls her and the bully she's fighting with "athletes". She does turn out to be good at sports and equally good in the classroom, impressing Watson and human!Doctor. Badass Bookworm in the making.
A Day in the Limelight: Unlike the original two-parter, this episode looks at the Power Trio through the eyes of a fifteen-year-old girl.
All Up to You: It all boils down to one teenage girl with a soul in a fob watch.
Axes at School: So... two kids are murdered by possession, just as in the original... and then you have those same two kids with guns on a high school campus. (Note that "Human Nature"/"Family of Blood" had nothing to do with American school issues, and that this story was based on the original two-parter.)
Badass Boast: "I've seen the Doctor. I've seen you with him, you and Dr. Watson. The three of you... You're like... fire... and ice... and everything terrible and wonderful about light and darkness. And the Doctor... He's ancient — I've seen that. Burning at the centre of time. Able to see the turn of the universe."
Changed My Jumper: Played with. Holmes and Watson are undercover, and Holmes is the consummate professional at undercover work. They're just two British gents who happen to be high school teachers... except that Beth doesn't buy Holmes's unchanged accent.
Creepy Child: Daughter of Mine, who possesses the body of Beth's best friend.
Although part of the story from Beth's POV is uncovering the Hidden Depths in her new teachers, the story from Holmes's POV is partly about seeing the Hidden Depths in Beth.
Fifteen-year-old stuns a police officer and takes control of the car. Oh yeah.
Jumped at the Call: Beth is all set for adventure (it's in her blood), and the Doctor tells her "not yet". She'll have to wait two more years in her own timeline, which is a couple of months for the Doctor and Holmes and over a year for Watson.
Karmic Death: Son of Mine is the one member of the family who shoots someone onscreen. Watson ends up having to shoot him to keep him from taking the watch from Beth.
Mid-Season Twist: This isn't the first time we've had a heroine in the season, but it is the first time that an episode happens largely from said heroine's POV. That being said, this episode is the one that's the game-changer, because it introduces Beth who, two episodes later, becomes one of the main characters.
You Are Not Ready: The reason the Doctor tells Beth "not yet", calling her "too young".
the girl who was once my best friend.