James falls in deeper with the Children of Liberty in his efforts to meet Agent Liberty. Meanwhile, Supergirl and Manchester Black follow a lead on Agent Liberty’s location, but things take a dark turn. Lena kicks off her first set of trials.

In the wake of Lex Luthor's return, the show flashes back to what he's been doing for the last two years and how his secret machinations and plans have affected Supergirl and Lena.

Supergirl, Alex, and Brainiac thwart an alien attack while William investigates Kara. J'onn J'onzz and Kelly use Obsidian tech to solve a problem.

While a new villain is under arrest at the DEO, Supergirl uses him to try and understand who is responsible for the recent attacks. Meanwhile, Andrea and Lena think back on their tumultuous past.

As Supergirl tries to thwart a Toyman copycat, Winn Schott returns from the future.

Nia’s roommate, Yvette, is attacked by a man targeting Dreamer because he doesn’t like that Dreamer is transgender and wants her to quit being a superhero. Determined to protect her community from additional harm, Dreamer refuses to give into his threats and puts herself in the line of fire to stop him. Supergirl stands by Dreamer and enlists additional help from Brainy. Meanwhile, Alex, J’onn and Kelly attempt to rescue a man stuck inside a virtual reality escape room.

Supergirl makes a new ally. Lena and Lex battle for control of Luthor Corp.

As Supergirl and Zor-El make their return to National City, they are determined to keep the Phantom Zone behind them and enjoy being superheroes together. Unfortunately, their overzealous efforts backfire, creating a whole new threat to National City.

When Lex Luthor appears by Nyxly's side, Supergirl and team must deal with the emotional fallout of facing their two biggest foes at the same time. Alex makes plans for the perfect proposal to Kelly, but work keeps getting in the way.