- "Imagine my excitement when one of my fighters told me about Slaver's Moon. I jumped at the opportunity to help expand it's market."
- —Veronica Sinclair
Kara is moved by the story of a missing woman named Izzy and decides to investigate despite Snapper Carr’s order to leave it alone. Kara takes Mon-El with her to the last place Izzy was seen and the duo find themselves thrust through a portal to another planet, Slaver's Moon, where the downtrodden are sold as slaves. The leader of the trafficking ring is none other than Roulette. To make matters worse, Slaver’s Moon has a red sun, which means Kara and Mon-El are stripped of their powers and stuck on the planet with no way home. Meanwhile, back on Earth, Alex blames herself for Kara’s disappearance, fearing she's become too focused on her new relationship with Maggie and too complacent in watching out for her sister.
- The episode's title is a reference to the unproduced Superman movie Superman Lives. The episode's director, Kevin Smith, wrote the original screenplay for the film.
- An Earth Thirty-Eight Dominator can be seen when Supergirl, Mon-El, and the rest of the humans are captured. Kara mentions that she hates the Dominators, indirectly referencing the 4-night crossover event, in which she went to Earth One and fought the Dominators of that universe.
- The alien Jo said to Kara and Mon-El that he was cooking a "Thanagarian Snare Beast". This is a reference to Kevin Smith's un-produced movie Superman Lives, which was intended to include a giant spider monster with that name.
- When Winn Schott is left alone at the portal, he says a few times, "I am not a red shirt". In the Star Trek franchise, a "redshirt" is a term used by fans to denote a character wearing a red Starfleet uniform that are killed, typically expendable characters with little significance to the plot besides their death.
- When Kara asks Winn why he is wearing sun glasses, he answers "The future is so very bright". This might be a reference to the Timbuk3 song "The Future's So Bright, I Gotta Wear Shades".
|Supergirl season 2|
|"The Adventures of Supergirl" • "The Last Children of Krypton" • "Welcome to Earth" • "Survivors" • "Crossfire" • "Changing" • "The Darkest Place" • "Medusa" • "Supergirl Lives" • "We Can Be Heroes" • "The Martian Chronicles" • "Luthors" • "Mr. & Mrs. Mxyzptlk" • "Homecoming" • "Exodus" • "Star-Crossed" • "Distant Sun" • "Ace Reporter" • "Alex" • "City of Lost Children" • "Resist" • "Nevertheless, She Persisted"|