An ancient demonic entity, he first possessed veteran marine Santino via markings on a wall inside of a cave located in the Diyala Province of Iraq. After returning from the war, Jungler turned Santino into a vicious serial killer, targeting Santino's former war partners and their families. He forces one of his partners' wives, Jena Crenna to throw her baby to the lions at the Bronx Zoo, which resulted in her being hospitalized in a mental institution. Officer Ralph Searchie and Priest Mendoza later discover that Jena was in fact possessed by lesser demons sent to earth by a more powerful evil force, The Jungler Demon. Worried about his family's safety, Ralph began to search for Santino with the help of his partner Butler and Mendoza, they eventually found him in an apartment building, where they were attacked by Jungler and now a fully-possessed Jimmy Tratner, the attack resulted in Butler's death at the hands of Jungler. Jungler eventually abducts Searchie's wife and daughter. Seeing exorcism as the only solution to find them, an exorcism is performed and Jungler is banished, allowing the real Santino to reveal their location.
- Jungler is theorized to be a demon from both Christian and Pagan theology.