(Dan Reynolds. Photo via Instagram.)

Dan Reynolds, frontman of the rock band Imagine Dragons, will star in the documentary “Believer,” which follows his journey as an advocate for LGBT Mormons.

“Believer” chronicles Reynolds, who is Mormon, and out Neon Trees lead singer Tyler Glenn, a former Mormon, as they plan the LoveLoud Festival, a charity concert last summer in Utah that raised money for at-risk LGBT youth.

The film debuted at the Sundance Film Festival and received a standing ovation.

Reynolds told the Washington Post he hopes the film can change the way the Church of Jesus Christ of Latter-day Saints views the LGBT community.

“These kids are being told their most innate sense of being is sinful,” Reynolds says. “Shaming is so destructive.”

Reynolds recently apologized for preaching anti-gay Mormon teachings when he accepted the Hero award for the Trevor Project in June.

“I hold regret about that until this day. I wish I could re-knock on those doors and tell them I was wrong. I can’t do that. All I can do is come forward to you today and say I’m sincerely sorry,” Reynolds said at the time.

“Believer” airs on HBO this summer.