Set around Christmas time, Angel Fire East, third novel in Terry Brooks's allegorical Word & Void series, opens with protagonist John Ross having had a futuristic vision of a Knight of the Word being crucified, and the knight looked a lot like him. Knights of the Word have the task of maintaining the balance in the world between the Word, which represents goodness and light, and the Void, which represents evil and darkness. In John's vision, the knight tells him that a gypsy morph was being created, which is a powerful, magical tool that either the Word or Void can use to its advantage depending on who accesses it first.
Using a map John's vision gave him, he is able to find the gypsy morph before the demons following him find it. The gypsy morph transforms into the figure of a boy at the age of four who only says the name "Nest." A woman named Nest Freemark is an Olympic gold medalist and a friend John has not seen for 10 years. John heads to Hopewell, Illinois, where Nest lives, to see if Nest can help. However, Gask, the allegorical equivalent of Satan, and his demon helper named Penny reach Nest before Ross can.
Though Gask and Penny try to tempt Nest into deciding not to help John when he finally arrives, Nest refuses to listen and heads to church for an advent service. When she returns to her house, she finds her childhood friend Bennett Scott and Bennett's daughter, called Harper, sitting on her porch. Bennett says she has come to Hopewell believing Nest will help Bennett with her drug addiction, and Nest invites Bennett and her daughter to stay as long as they need to. After Christmas caroling, the three return to Nest's home one more time to find that John has arrived with the gypsy morph, which is still in the shape of a little boy John calls Little John.
That night, the five characters face many temptations and adversities delivered by Gask and Penny. The worst of those temptations leads Bennett to give way to her drug addiction, leading to an overdose and her death. In addition, on Christmas Eve, Gask and Penny kidnap Harper and Little John. The battle between John, Nest, and the evil forces results in John being killed. The novel ends with the gypsy morph entering Nest's womb as a child waiting to be born, and Gask backs off, not knowing what has happened to the gypsy morph and believing Nest no longer has it.