Shay is attending a
purity ball with her father Kyle and her rebellious half-sister Jo. She knows neither person very well as she only met them after the death of her mother two months prior. Jo is dismissive of the retreat, seeing it as
patriarchal, antiquated nonsense, while Shay hopes to use it to grow closer to her dad. At the retreat, Shay and the other girls listen to sermons by conservative Pastor Seth about
Lilith, who he portrays as lusty and sinful since she was created equal, and
Eve, who he depicts as symbolic of women's weakness. Later that night, Shay is included in a ritual to summon Lilith, which Jo secretly holds every year with her cabin mates. This year's ritual appears successful, and Shay starts experiencing strange phenomena, prompting her to investigate the ritual. She discovers that it can only be successful if one of the participants isn't a virgin, and that the ritual culminates with Lilith possessing that woman's body. Shay finds that she strongly disagrees with the retreat's ideals and methods, telling her cabin mates, one of whom is Seth's daughter Lacey, that they should exert control over their own bodies and sexuality. Jo decides to lose her virginity to her boyfriend, only to be caught and captured by her father and Seth. At the purity ball on the following day, a distraught-ridden Jo admits to a worried Shay that Kyle had known about Shay since birth but deliberately chose to exclude her until now. Jo had kept this secret because she wanted her father's approval. This angers Shay, and when Seth tries to gather everyone to sign a
purity contract, Shay refuses. She confesses to lying about her virginity for Kyle's approval, but she says that she's not ashamed of her sexuality. Other girls stand up to their fathers and Lacey admits to not upholding her father's commands. She then kills herself with a gun Seth carried, unable to live with her feelings and the torture he put her through. Lilith enters the body of a pleading Shay and uses her powers to control and then kill the men before setting the retreat on fire, stating that she's watched women suffer for long enough. The girls are shown huddled on the floor before they are seen walking away to the woods, led by Lilith. ==Cast==