Crisis on Infinite Earths is a 12-issue American comic book limited series (identified as a "12-part maxi-series") and crossover event, produced by DC Comics in 1985 to simplify its then 50-year-old continuity. The series was written by Marv Wolfman and illustrated by George Pérez (pencils/layouts), along with Mike DeCarlo, Dick Giordano, and Jerry Ordway (who shared inking/embellishing chores). The series removed the concept of the Multiverse in the fictional DC Universe, and depicted the deaths of such long-standing superheroes as Supergirl and the Barry Allen incarnation of the Flash. As such, it is one of the most important events in the DC Universe, and continuity in the DCU is typically divided into pre-Crisis and post-Crisis periods.
The title of the series was inspired by earlier crossover stories involving the multiple parallel Earths of the Multiverse, such as "Crisis on Earth-Two" and "Crisis on Earth-Three", but instead of lasting two to five issues and involving members from many superhero teams from many parallel worlds, it involved virtually every significant character from every parallel universe in DC's history. It in turn inspired the titles of four subsequent DC crossover series: Zero Hour: Crisis in Time (1994), Identity Crisis (2004), Infinite Crisis (2005–2006), and Final Crisis (2008).