In 1976, in the sealed back bedroom of a home in Washington state, authorities found the decomposing body of three-year-old Davey Weilbacher, beaten to death nearly two months prior. Beyond that bedroom door was self-proclaimed prophet Leon Cunningham, who convinced his sheltered cult of family and friends—including Davey’s lost young mother—that the boy was possessed by the Devil. Exorcism was the only way to save him, leading to a ritualistic campaign of abuse, control, unimaginable violence, and murder. Gregg Olsen delivers a meticulously researched account of religious manipulation, domestic terror, and one woman’s fifty-year journey to finally tell the truth about what happened behind closed doors in that modest little yellow house in Yakima.