"Crisis on Infinite Earths" is the sixth Arrowverse crossover event, featuring episodes of the television series Supergirl, Batwoman, The Flash, Arrow, and Legends of Tomorrow on The CW. The Supergirl, Batwoman, and The Flash episodes aired in December 2019 while the Arrow and Legends of Tomorrow episodes aired in January 2020. The events of the Black Lightning episode "The Book of Resistance: Chapter Four: Earth Crisis" and a two-issue comic book with characters and concepts unused in the live-action episodes also tied into the event.

The Arrowverse is an American superhero media franchise and shared universe that is centered on various interconnected television series based on DC Comics superhero characters, primarily airing on The CW as well as web series on CW Seed. The series were developed by Greg Berlanti, Marc Guggenheim, Andrew Kreisberg, Geoff Johns, Ali Adler, Phil Klemmer, Salim Akil, and Caroline Dries. Set in a shared fictional multiverse much like the DC Universe and DC Multiverse in comic books, it was established by crossing over common plot elements, settings, cast and characters that span six live-action television series and two animated series.