The New 52 is a 2011 revamp and relaunch by DC Comics of its entire line of ongoing monthly superhero books, in which all of its existing titles were cancelled, and fifty-two new series debuted in September 2011 with new first issues. Among the series being renumbered are Action Comics and Detective Comics, which had previously retained their original numbering since the 1930s. Touted as a large publishing event following the conclusion of the "Flashpoint" crossover storyline, DC's relaunch entails changes to both the publishing format and fictional universe to entice new readers. Publishing changes include same day release of physical comics with digital platforms, all DC Universe titles being cancelled and restarted at a new first issue, characters from the former Wildstorm imprint being absorbed into the DC Universe, and new titles being released to bring the number of ongoing series being published on a monthly basis up to fifty-two. Changes made to DC's internal continuity are intended to make characters more modern and accessible
In late July 2011, DC released The New 52, a free preview book giving solicitations and previews of all of the new titles launching from August 31, 2011. Notable continuity changes shown include Superman's two new looks: one of which consists of jeans, a blue T-shirt with the "S" logo and a cape, and the other consisting of Kryptonian battle armor that resembles his classic costume. Other notable changes include the integration of the Wildstorm imprint's characters into DC continuity, with Martian Manhunter as a part of the new Stormwatch team in the relaunched Stormwatch series.
Justice League was the first book of the relaunch, with the first issue released on August 31, 2011. Geoff Johns and Dan DiDio revealed that the first story arc takes place five years prior to the present, during the dawn of superheroes, and details the first meeting of the Justice League members and the formation of the team.
The initial run of first issues show a universe in which superheroes have only appeared within in the past five years and are viewed with suspicion and hostility, with Superman and Batman being pursued by the police five years ago at the start of their careers. In the present day, some organizations, such as the United Nations and the United States government, seek to exploit and control the superheroes through groups such as the Justice League International and the Justice League of America.
Various character changes have also occurred, such as Barbara Gordon recovering from the paralysis inflicted upon her by the Joker's bullet in The Killing Joke and returning to crimefighting as Batgirl, while several characters, such as Starfire, Guy Gardner, and Tim Drake, have had their origins significantly changed.