John Constantine (Keanu Reeves), a habitual smoker and lover of sarcasm, has a special talent that allows him to see angels, demons, and mixed race people. Angels must stay in heaven, devils must stay in hell, and the only beings who can enter this world are mixed race. According to the rules agreed upon by God and the devil, angels and devils cannot directly influence humans. Even angel and demon hybrids can only persuade humans. Constantine is a contract contractor in charge of returning mixed-bloods who have violated the rules and directly affected humans to heaven and hell.


Constantine, who was exorcising demons as usual, realizes that demons that cannot come to this world by rules are at large. At the same time, he is diagnosed with lung cancer. Gabriel, a mixed-race angel, hopes to prove that humans are worthy of God's love. He hopes to survive this hellish world and become a truly great being. Gabriel believes that humans who receive God's forgiveness simply through repentance receive excessive privileges. It's too easy. Therefore, she decided to help Mammon, the son of Satan, who was trying to come to this world. Mammon can come to this world only with the help of God. Now it's up to John Constantine to save the world.