Alexander Joseph Luthor is a supervillain in The CW's Arrowverse, based on the character of the same name created by Jerry Siegel and Joe Shuster. Adapted for television in 2017 by Glen Winter and Greg Berlanti, he made his first appearance in the Supergirl episode "Luthors". Both Aidan Fink and Jon Cryer portrayed versions of the supervillain, with Aidan Fink portraying a young Lex Luthor and Jon Cryer portraying Lex as an adult.