Two Fundamentalist Mormon brothers murdered their sister-in-law and 15-month-old niece in Utah on July 24, 1984. They claimed God told them to commit the crimes via a revelation. 

The story of those murders unfolds in “Under the Banner of Heaven,” a new FX on Hulu true crime television show set to premiere April 28. The series takes on the same name as the investigative non-fiction book by Jon Krakauer (2003) and  follows the lead detective’s shaken faith in Fundamental Mormonism after connecting the murders to the Church.

Krakauer backs up his reporting with a deep-dive into the Latter Day Saints church, beginning with the life of Joseph Smith, founder of Mormonism. Krakauer also takes on the main differences in the modern LDS church and Fundamental Mormonism, chief among them the LDS’s rejection of polygamy. Smith’s belief in plural marriage ultimately led to his murder and decades of violence between Mormons and Gentiles. 

The fictionalization of the FX on Hulu series begs the question of how the show will incorporate the uncomfortable history of the Mormon church and how its belief system influenced Ron Lafferty, a self-proclaimed prophet, to feel called to murder via God. “Under the Banner of Heaven” stars Andrew Garfield (“The Amazing Spider-Man”) as Detective Jeb Pyre and Daisy Edgar-Jones (“Normal People”) as murder victim Brenda Lafferty. 

The series includes four episodes, two on April 28, one on May 5 and the last on May 12. “Under the Banner of Heaven” can be streamed on Hulu through FX and on Disney+(Star) in international markets.

Following the detective throughout the plot also leaves some holes in the story Krakauer cultivated in his reporting. This narrative makes the inclusion of modern-day Fundamental Mormon communities more difficult to portray. Without portraying the incest and abuse that occurs in these towns, it is almost impossible to understand the psychological conditions that cultivated an environment of such extreme influence via the Fundamental Mormon Church.

The screenplay adaptation of Krakauer’s book was sold in 2011 and the mini-series was announced in June 2021. The show is rated TV-MA for its mature content.