In the pre-crisis era Lena Luthor was the youngest sister of Lex Luthor and she lived with her father, Jules. When Lex became a criminal, the family changed their names to Thorul.
In this universe Lena Luthor is the little sister of Lex Luthor and daughter of Lionel Luthor. Unlike the other version of Lena she grew up with Lex until he left Smallville. Lena is also an invalid and her daughter Lori is always taking care of her. When Lori became friends with Superboy and eventually kissed him, she brought him to visit her house. A few minutes later Lex appears with kryptonite in his hands claiming that he can cure his little sister, Lex cures Lena but then undoes his cure just to prove to Superboy that he can kill Superman.
Nowadays Lena is under care of the Wayne Enterprises doctors.
Lena Luthor works in her big brother Lex's private labortory based under Lexcorp Tower. She is still in her wheelchair and it is believed that Lex knew he could not heal her so he left home. The truth is Lex tried and failed to heal Lena and Lex left home instead of being reminded of his failure.
Major Story Arcs
The Amazo Virus
Lena is present when a battle between the Justice League and Neutron, accidentally releases the Amazo Virus from Lex Luthor's private lab.
When Lex Luthor and Superman enter the laboratory, she shoots her brother from behind and uses a Darkseid motherbox, teleporting them both out of the lab.
Lena First appears in the 4th season of the TV show Superboy. She is the only person Lex Luthor has ever loved. When he finds out she died in an accident he decides to destroy the world. Clark and Lana begin to look into her death when they notice her utilities were shut off before she died. It turns out Lena faked her own death to get away from the stigma of being Lex's sister. She returns to his side to help convince Lex to stop his insane plot. She is played by Jennifer Hawkins.
Lena appears during season 8 of Smallville under the name of Tess Mercer, originally a mysterious woman who gains control of Lex's assets following his death. She is obsessed with finding out what happened to Lex Luthor, and begins to research Lex's obsession with Clark. Throughout her time on the show Tess becomes a trusted friend of Clark. During the final season Tess begins researching her past eventually finding out that she was born Lutessa Lena Luthor, abandoned by Lex's father like he did with his other illegitimate son Lucas (revealed in season 2). She is played by Cassidy Freeman.
During the 2nd season Lena moves to National City where she appears to be trying to redeem the Luthor name. Many of her actions are still clouded in mystery but She has befriended and helped Kara on a number of occasions including saving her from Lena's own mother's attempt to kill her. She is played by Katie McGrath.
DC Super Hero Girls
Lena debuts in the episode "Batnapped" of the 3er season. She is voiced by Romi Dames.
DC Super Hero Girls: Intergalactic Games
Lena Luthor works in the school, under the alias of Lena Thurol, as the IT girl while secretly plotting against the school. When the Metal Men are defeated, Lena recovers Platinum and turn her into her minion. She starts building and army of kryptomites, stating that the heroes has cause more problems that solutions, leading to the attack of several villains. She believes that the heroes are not a welcome presence (Though is later revealed that the citizens of Metropolis don´t think that way).
She uses a piece of technology she steals from Will Magnus and makes Platinum almost sentient.
During the final game, she attacks the school, revealing that she is Lena Luthor (not Thurol). She claims she has been working in this for a long time, and even get bald from the kryptonite's radiation.
She is defeated by the heroes, with the help of Platinum who sees the good in the heroism, and is sent to Belle Reve.
On her way to the prison it´s revealed that she has been working with Brainiac. Due to her failure, Brainiac must reveal himself and tries to kill Lena.
When the heroes are unable to defeat Brainiac, Big Barda realises that if Lena has been working with him, she must know some weakness. They reach out Lena, but she refuses to help them.
She is voiced by Romi Dames.
LEGO DC Super Hero Girls
Lena debuted in Season 1, Episode 1 "Body Building".
Lego DC Super Hero Girls: Brain Drain
Lena Luthor appears in the film as antagonist, with Romi Dames reprising her role.