Eight-year-old Prudence Boyd and her younger sister Grace are visiting East Winder, Kentucky for the weekend. They are traveling with their father, Reverend Yancy. He is under consideration for a minister position at First United Methodist (FUM), the local church. The are rumors that nearby, there lives a young boy—Ryan—who became possessed by a demon in Africa, where his parents did missionary work.  Prudence and Grace prepare their costumes for the evening Halloween party at FUM. The children have been asked to dress as Bible characters, so Grace plans to be John the Baptist—ketchup blood, head on a platter, and all—and Prudence plans to be Salome, the sensuous dancer that demanded John's beheading.  During a casual conversation, Miss Moberly, who is hosting the Boyds, mentions that Mrs. Boyd is sick; Prudence corrects her, believing her mother is simply "tired." Joyce Boyd is, in reality, chronically depressed and bedridden. At dinner, Miss Moberly reveals that her own adult daughter broke her heart by leaving the church and becoming an atheist.  At the Halloween party, the adults are shocked by the goriness of Grace's costume and the "inappropriateness" of Prudence's costume. Once again, they mention her mother's illness; Prudence becomes even more upset, insisting that her mother is tired.  Prudence and Grace escape from the adults, running into the dark heart of the church basement. There, they stumble upon Ryan's botched exorcism; Ryan runs out of the room, where he meets Prudence and Grace.  In the dark, Prudence and Grace comfort Ryan. To calm him down, they tell him the story of Salome. Prudence begins to hum softly and perform Salome's dance. Soon, Ryan starts to smile and laugh. When the adults find them, Prudence simply closes her eyes and keeps dancing, even though she knows she will be punished for her actions.