Alexander Joseph "Lex" Luthor is a fictional character supervillain who appears in comic books published by DC Comics. He is the archenemy of Superman, but given his high-status as a supervillain, he has become a major adversary of Batman and other superheroes in the DC Universe. Created by Jerry Siegel and Joe Shuster, he first appeared in Action Comics #23 (April 1940). Luthor is described as "a power-mad, evil scientist" of high intelligence and incredible technological prowess. His goals typically center on killing Superman, usually as a stepping stone to world domination, which he has articulated as a stepping stone to domination of the universe, demonstrating a truly unbridled level of megalomania. Though he periodically wears a powered exoskeleton, Luthor has traditionally lacked superpowers or a dual identity.
The character was originally depicted as a mad scientist who, in the vein of pulp novels, wreaks havoc on the world with his futuristic weaponry. In his earliest appearances, Luthor is shown with a full head of red hair; despite this, the character later became hairless as the result of an artist's mistake. A 1960 story by Jerry Siegel expanded upon Luthor's origin and motivations, revealing him to be a childhood friend of Superman's who lost his hair when a fire destroyed his laboratory; Luthor vowed revenge.
Following the 1985 limited series Crisis on Infinite Earths, the character was re-imagined as a Machiavellian industrialist and white-collar criminal, even briefly serving as President of the United States. In recent years, various writers have revived Luthor's mad scientist persona from the 1940s. The character was ranked as the 8th Greatest Villain by Wizard on its 100 Greatest Villains of All Time list. IGN's list of the Top 100 Comic Book Villains of All Time ranked Luthor as #4. Luthor is also described as a "megavillain" by comic book critic Peter Sanderson. These supervillains are genre-crossing villains who exist in adventures "in a world in which the ordinary laws of nature are slightly suspended"; characters such as Professor Moriarty, Count Dracula, Auric Goldfinger, Hannibal Lecter, Doctor Doom and Darth Vader, also fit this description.