At the end of the 13th episode of the second season, Mon-El (played by Chris Wood) and Supergirl (Melissa Benoist) officially become a couple.

Early on, Supergirl's greatest nemesis was Lesla-Lar, who lived in the bottle city of Kandor and had an uncanny resemblance to Kara Zor-El. Lesla-Lar was jealous of her look-alike's freedom on Earth and devised a weapon that robbed the Maid of Steel of her powers (Action Comics #279, 1961).

The film stars Faye Dunaway (Selena), Peter O'Toole (Zaltar), and Helen Slater (Supergirl). Although the film failed to impress critics and audiences alike, Slater was nominated for a Saturn Award for Best Actress.