Detectives Jeb Pyre (Andrew Garfield)  and Bill Taba (Gil Birmingham) investigate the brutal, sinister murders of an LDS woman, Brenda Wright Lafferty and her baby daughter in Utah’s typically serene Salt Lake Valley in 1984. With a lead suspect in custody, the investigation uncovers more ominous questions than answers as the hidden history of the once admired Lafferty family is exposed. The ongoing investigation leads Pyre and Taba to unearth information that challenges Pyre’s own faith, and draw more Laffertys into suspicion and custody. Pyre uncovers details of the Lafferty family’s fundamentalist beliefs, sparking a search for missing Lafferty brothers, Ron and Dan and putting Pyre at odds with his own church leaders. With evidence now pointing squarely toward fundamentalist Mormonism, Pyre turns to LDS Church leaders for guidance but is met with roadblocks. Undeterred, he discovers a list of names Brenda’s killers plan to murder next.