
Lena Luthor is a major character in the CW series Supergirl. She serves as a supporting protagonist in Season 2, a major protagonist in Seasons 3-4 and 6, and the central antagonist of Season 5.
She was originally a supporting character, but after she found out that Kara Danvers had being lying to her about her identity as Supergirl, she becomes a major threat to her and the Superfriends. However, Lena redeems herself by the end of the season and amended their friendship.
Lena is the paternal estranged half-sister of Lex Luthor, daughter of Lionel Luthor, and the estranged adoptive daughter of Lillian Luthor. She is also the ex-girlfriend of the late Jack Spheer and James Olsen, and the best friend turned (former) enemy of Kara Danvers.
She is portrayed by Katie McGrath, who also portrayed Morgana Pendragon in Merlin. When she was young, she was portrayed by Camille Marty, Samantha Davis, and Lucy Loken.