How Pearl Jam's Jeff Ament crafted Under the Banner of Heaven's haunting soundtrack

Jeff Ament may be best known for performing on stage — but now, the Pearl Jam bassist is bringing his music to the screen.

Ament composed the music for Andrew Garfield's chilling true crime series Under the Banner Heaven, his first time writing an original score for film or TV. Like the show, Ament's soundtrack can be both moving and unsettling, mixing atmospheric piano and heavy guitar for a haunting sound.

"I've always thought that I was going to make some ambient records, and I've done pieces here and there over the years," Ament tells EW, speaking by phone last week in between performances for Pearl Jam's North American tour. "But I've never gone all in on a project, and this felt like the perfect one."

The musician says he's long wanted to score a film or TV show, but the right project never came along. That is until recently, when he was invited to pitch to Under the Banner of Heaven creator Dustin Lance Black, who was adapting Jon Krakauer's nonfiction bestseller. Like the book, the show chronicles the real-life double-murder case of Brenda Lafferty and her infant daughter, while also exploring the case's ties to extremist Mormon fundamentalism and the very history of the Church of Latter-day Saints.

In many ways, Under the Banner of Heaven was the perfect project for Ament: He'd first read the book years ago and has long been a fan of Krakauer, ever since he started reading the author's work in Outside magazine. (Coincidentally, Ament's Pearl Jam bandmate Eddie Vedder also did the music for Into the Wild, another adaptation of a Krakauer book.)

Plus, Ament adds, he was intrigued by how Under the Banner of Heaven raised questions of faith and fundamentalism, tackling a complicated true story with nuance and empathy. As someone who was raised Catholic, he explains, he was particularly drawn to how the show explored often contradictory religious themes. "I had my own sort of religious unraveling," Ament says. "There were a lot of things about the story that I felt like I could tap into from an emotional standpoint."

Black himself is a longtime Pearl Jam fan, and the showrunner says that both he and Ament wanted the score to feel as haunting and as heavy as the rest of the series. "I felt like this show needed to feel like it had the tension of a true crime thriller, but it also needed to feel bolted to the Earth," Black adds. "That was something I felt Jeff would be able to bring."

Last year, Ament gathered at his home in Montana to begin recording with collaborators Josh Klinghoffer, Josh Evans, and John Wicks. Even before they saw any footage, they began experimenting with ambient loops and tones, poring over the scripts and Krakauer's book for inspiration.

One of his biggest challenges was how to juggle the show's ever-shifting story. Much of the series is set in 1984, as fictional detective Jeb Pyre (Garfield) investigates Brenda's murder, slowly uncovering new details about her life. But there are also flashbacks to the 19th century, chronicling major moments in Mormon history featuring figures like Joseph Smith or Brigham Young.

"The historical montages were trickier because we didn't want to go into full banjo mode," Ament explains. "I think when you see those sorts of movies, that's kind of what happens, where they're playing the instruments of the time or whatever." He and his fellow musicians experimented with using decades-old instruments to age the sound, while still maintaining the show's rock vibe. "It allowed us to go into vintage sounds without getting into, like, Western music," he adds.

In fact, Black had to occasionally encourage Ament to embrace a harder, more rock 'n roll tone. "There were times when we were leaning pretty hard on the ambient thing," Ament says with a laugh. "Sometimes [Black] was like, 'I want it to be heavier. I want it to be more rock.' Which was cool! Initially, we were trying not to be too rock, and he was so great at guiding us without over-directing it."

Ultimately, Ament says he hopes Under the Banner of Heaven is just the first of many scores he'd like to write. (Although he jokes that between him and Vedder, the band has made an unofficial promise to only score adaptations of Krakauer books.)

"It's a hard story to tell," Ament adds of Under the Banner of Heaven. "It's hard to incorporate so much history in a handful of montages in seven episodes. So, I hope anybody interested in the historical part of it is going to come away knowing a lot of things about the relatively short history of Mormonism."

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