- Broken Tears: Murphy cries when he begs Clarke not to sacrifice Emori.
- Double Standard: When Emori tries to destroy the radiation chamber so that she can't be tested, the group detains her and handcuffs both her and Murphy to a pole so they can't escape. When Abby actually destroys it, no one makes any effort to stop her (seemingly because it's Clarke going in the chamber now instead of Emori.)
- Fantastic Racism: Roan has fewer qualms than the rest of the group over testing Emori due to his culture's feelings about radiation mutations. Raven calls him out on it.
- Funny Background Event: When Bree is trying to convince Bellamy to dance with her, the camera briefly flashed to Jasper hilariously egging Bellamy on from a distance.
- He Who Fights Monsters: As Raven points out, the group's actions are nearly identical to those of Mount Weather from season 2: the are forcibly extracting bone marrow from someone in order to save their people, and testing the radiation solution on someone even if it costs their life.
- Heroic Sacrifice: Clarke tries one by taking the bone marrow in Emori's place. Abby stops her before she can go through with it.
- I Am Begging You: Said word for word by Murphy when he asks Clarke to spare Emori.
- I Owe You My Life: Invoked. While pleading with Clarke to spare Emori, Murphy reminds her that he saved her by pumping Ontari's blood in the season 3 finale.
- Mama Bear: Abby, naturally.
- Nice Job Breaking It, Hero!: Literally. Abby flips out when it looks like Clarke is going into the radiation chamber and destroys it, effectively eliminating the Nightblood solution they've been working toward the last few episodes.
- The Bus Came Back: Easy to miss, but the girl who approaches Bellamy is Bree, one of the girls he slept with during the 100's first days on Earth.
- Token Evil Teammate: Played with. Clarke and Abby seem willing to use Emori's status as this (after they discover her lie from last episode) as justification for testing her but neither one really believes it. Emori and Murphy, meanwhile, are clearly portrayed as the sympathetic party when they plead with Clarke, Raven, and the others not to sacrifice Emori. What's more, while the two have been shown to be selfish characters on their own, their relationship is easily one of the strongest and most loving relationships on the show and their loyalty to each is other is right up there with the show's other key relationships.
- Basically it's the show's usual Gray and Gray Morality at work.
- What the Hell, Hero?: Murphy calls Clarke out on her willingness to play God and to sacrifice Emori for "the greater good." He also reminds her that the only reason she is alive is because he saved her.
- You Need to Get Laid: More like "You need to get high," but this is Jasper's solution for Bellamy's season-long guilt trip. Although, Bree seems to imply this trope straight...
Recap / The 100 S 04 E 08