Plot
Filmmakers Iris and Daniel document Cotton Marcus, a reverend living in Baton Rouge, Louisiana, who seeks to delegitimize exorcisms. Marcus, who lost his faith after the birth of his disabled son, is accustomed to performing fake exorcisms on individuals who believe they are possessed. He accepts an exorcism request sent by Louis Sweetzer, a farmer who suspects his daughter Nell is possessed by Satan.
Marcus claims that Nell is possessed by Abalam, a powerful demon who defiles the innocent. Conducting the phony exorcism, he convinces her family that he has driven out the demon and leaves, believing he has cured her of a mental state that was misdiagnosed as possession. That night, Nell inexplicably appears in Marcus' motel room, visibly unwell. He takes Nell to the hospital, where it is concluded that she is in perfect physical condition. He visits Louis's former pastor, Joseph Manley, who tells him that he hasn't seen Nell in 3 years. Louis takes Nell home but chains her to the bed after she cuts her brother's face with a knife.
Marcus frees Nell, and the hospital calls back to inform that she is pregnant. That night, Nell brutally smashes a cat to death in the barn. Iris and Daniel discover her morbid paintings, which depict Marcus before a large flame with a crucifix, Iris dismembered, and Daniel decapitated. Louis insists that Nell is a virgin and has been impregnated by the demon. Offended at Marcus's insistence that a demon is not involved, he demands that the crew leave and alludes to intending to kill Nell. The crew tries to escape with Nell, who attacks Marcus. Marcus offers to attempt a second exorcism as Nell begs her father to kill her.
During the exorcism, Nell manifests into "Abalam" and asks Marcus if he wants a "blowing job.” Marcus challenges that a demon would know the actual name of the sex act and concludes that Nell is not possessed, but a disturbed girl. Nell anguishes over losing her virginity to a boy named Logan, which Louis rejects. The crew meets Logan, who explains that he is gay and only had a brief conversation with Nell during a party at Manley's house 6 months prior; They realize Manley was lying about having not seen Nell and return to the Sweetzer farmhouse, which they find empty and covered with occult and countercultural symbols on its walls.
In the woods, the group sees a fire and a congregation of hooded cultists led by Manley. Louis is bound, gagged, and blindfolded while hooded figures pray around an altar, atop which Nell is bound. She gives birth to an inhuman child. Manley throws the child into the fire, which causes the fire to grow as demonic roars emanate. Marcus, his faith restored, grabs his cross and rushes toward the fire to combat the evil. Iris and Daniel flee; Iris is killed with an axe by a member of the congregation, while Nell's brother decapitates Daniel.
