Quick recap
Kara gets Superman's help against Project Cadmus, run by alien-hunting Lillian Luthor. Lena Luthor, Lillian's adopted daughter, takes over the family company and becomes friends with Kara. Last season's pod carried Mon-El, prince of Daxam, who becomes Kara's trainee and then boyfriend. James Olsen becomes the vigilante Guardian, and Alex comes out after falling for detective Maggie Sawyer. Queen Rhea, Mon-El's mother, invades Earth with the Daxamite fleet. Kara beats Rhea in a duel and disperses lead into the air, which is toxic to Daxamites. The invasion ends, but Kara has to send Mon-El away in a pod, which disappears into a wormhole.
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