Claim: Constantine is based on a comic book.

Constantine is a 2005 American-German occult detective action horror film directed by Francis Lawrence as his feature film directorial debut , starring Keanu Reeves as John Constantine , with Rachel Weisz , Shia LaBeouf , Tilda Swinton , Pruitt Taylor Vince , and Djimon Hounsou . With a screenplay by Kevin Brodbin and Frank Cappello , the film is based on DC Comics ' Hellblazer comic book , with plot elements taken from the `` Dangerous Habits '' story arc -LRB- issues # 4146 -RRB- and the `` Original Sins '' story arc .   The character of John Constantine was introduced by comic book writer/creator Alan Moore while writing the Swamp Thing , first appearing there in June 1985 . In 1988 , the character of John Constantine was given his own comic book title , Hellblazer , published by DC Comics . The `` Dangerous Habits '' story arc was written by Garth Ennis in 1991 .   The film portrays John Constantine as a cynic with the ability to perceive and communicate with half-angels and half-demons in their true form . He seeks salvation from eternal damnation in Hell for a suicide attempt in his youth . Constantine exorcises demons back to Hell to earn favor with Heaven but has become weary over time . With terminal lung cancer , he helps a troubled police detective learn the truth about her sister 's death while simultaneously unraveling a much larger and darker plot .   Constantine was released in the United States and Canada on February 18 , 2005 and in Hong Kong on February 8 , 2005 . The film received mixed reviews and was a box office success , grossing $ 230.9 million worldwide from a $ 100 million budget .