The archangel Michael is missing. His brother Gabriel enlists BA, the Bad Angel, to find him. BA is told if he completes the mission, he'd no longer have to guard Purgatory, which was his punishment for committing centuries of mistakes. Michael's blood is being used in a drug by a powerful being, known as the Peddler that makes humans homicidal. The purpose of the drug is to wipeout humanity. Because the Peddler is using vampires and rogue demons...