Alexander Joseph Luthor, Jr., otherwise known as Lex Luthor, is a major antagonist in the DC Extended Universe. He is the main antagonist of Batman v Superman: Dawn of Justice, and a minor antagonist in both Justice League and its 2021 director's cut, Zack Snyder's Justice League. He is also Superman’s arch-nemesis.
He is a megalomaniacal and psychopathic CEO of LexCorp and multi-billionaire who is one of the smartest people on the planet and has developed an unhealthy fixation with Superman, whom he views not as a hero but as an alien and an intruder. Thinking of himself as the superior one, Lex is obsessed with defeating and killing Superman through any means necessary, even using Batman. After Lex is incarcerated at Arkham Asylum, he soon breaks out and makes plans to create an "Injustice League" in order to combat the newly-founded Justice League.
He was portrayed by Jesse Eisenberg in his first villainous role.