A Wolf in Sheep's Clothing: Carol makes a brilliant performance to convince the Saviors that she's not a threat.
Beware the Nice Ones: Carol played the role of a nice, meek, and weak woman, just to bait the Saviors into ignoring her. When they did, she freed herself and Maggie and then they escaped, but not before killing the remaining Saviors AND their reinforcements.
Big Bad Wannabe: Paula does have some badass cred to her, but she is not as superior as she believes.
Chekhov's Gun: Carol walks in a very particular way when her hood is thrown over her head, and the shot shows only her feet. She's leaving tracks for Daryl, who, when they find them, says, "We found your trail."
The Saviors led by Bud, who were blown up by Daryl in "No Way Out," are referenced, first by Carol, and then by Chelle and Molly.
Maggie mentions death in childbirth, clearly remembering Lori's fate in "Killer Within."
Carol employs her Stepford wife persona that she used when she first came to Alexandria during the second and first halves of Seasons 5 and 6 respectively.
Carol mentions her "husband Ed" when trying to draw parallels between herself and Paula (after Donnie struck the latter).
The Load: Donnie, who was shot and is slowly bleeding to death from his gunshot wound.
Obfuscating Stupidity: Carol hid her true intentions and feigned spinelessness to make their captors underestimate her. It works and she's able to break herself and Maggie free at the first opportunity.
The One Guy: Donnie is the only male member of Paula's group of Saviors.
Villain Ball: Paula attempts to strike fear in Rick's group by making them wait until the hostage trade for hours. However, she completely disregards her ally Donnie bleeding out from his wounds and refuses to get him medical attention, a choice that causes Donnie's death. When he reanimates, Maggie turns him into a booby trap to use against them.
Paula makes a good point on criticizing Maggie for getting pregnant during a Zombie Apocalypse, as we've seen how helpless baby Judith can be in previous episodes.
Also, Chelle's words to Maggie.
Chelle: You're not the good guys. You should know that.