John Constantine, Hellblazer is an American contemporary horror comic-book series published by DC Comics since January 1988, and subsequently by its Vertigo imprint since March 1993, when the imprint was introduced. Its central character is the streetwise English sorcerer and con man John Constantine, who was created by Alan Moore and Stephen R. Bissette, and first appeared as a supporting character in Swamp Thing #37, during that creative team's run on that title. Hellblazer had been published continuously since January 1988, and was Vertigo's longest-running title, the only remaining publication from the imprint's launch. In 2013, the series concluded with issue 300, and was replaced by Constantine, which returned the character to the mainstream DC Universe. The original series was revived in November 2019 for twelve issues as part of The Sandman Universe line of comics, under the DC Black Label brand. Well known for its extremely pessimistic tone and social/political commentary, the series has spawned a film adaptation, television show, novels, and multiple spin-offs and crossovers.

Vertigo Comics was an imprint of American comic book publisher DC Comics started by editor Karen Berger in 1993. Vertigo's purpose was to publish comics with adult content, such as nudity, drug use, profanity, and graphic violence, that did not fit the restrictions of DC's main line, thus allowing more creative freedom. Its titles consisted of company-owned comics set in the DC Universe, such as The Sandman and Hellblazer, and creator-owned works, such as Preacher, Y: The Last Man and Fables.