Jason Momoa wanted his his war cry to sound suitably intense, so the actor brought on a vocalist from death metal band Archspire to coach him.

“See” is pretty metal: The Apple TV+ sci-fi series features plenty of violent battles, allusions to witches, and all manner of dystopian themes. Also, the show features two actual heavy metal musicians in a brief cameo, one of whom helped train star Jason Momoa to perform suitably bombastic war cries in the show’s pilot.

Much of the show’s first episode is dedicated to Baba Voss (Momoa) leading his village’s warriors against an invading army. Baba rallies his troops via an intense, spirited chant that includes all manner of horns, drumming, and formidable growling. It was a complicated sequence, and one that required outside counsel.

Momoa is a fan of British Columbia death metal band Archspire (death metal is characterized by its especially abrasive instrumentation and guttural vocals), and the actor invited vocalist Oli Peters to coach him on how to mimic his distinct vocal style for the show’s early troop rallying scene.

Peters discussed the experience in a recent IndieWire interview and noted that the “See” crew included blind and low vision individuals, one of whom was able to obtain his emails through an audio device he’d play at high speeds. The fast pace of the audio recording was unintelligible to everyone else, but its unique sound inspired Momoa to incorporate the style of speech into his in-show rallying cry.

There’s no shortage of metal bands with unintelligible and suitably forbidding vocals, but Archspire tends to stand out due to Peters’ signature fast-paced style of growling. Momoa, already an Archspire fan, reached out to the band through a mutual acquaintance who worked in the makeup department on “See” around a year before Apple TV+ launched, according to Peters.

Even for a veteran actor, mimicking death metal vocals is no easy task—singing in a harsh vocal style can cause long-term health issues if done incorrectly—but Peters said Momoa took quickly to the unique style of singing during their on-and-off practice sessions.

“Jason has such an interest in music and has done aggressive acting scenes before, so he was a quick learner for this,” Peters said. “We spent time getting him familiar with what the vocal style is and were messaging back and forth while Archspire was on tour. When we hung out on sets, in between takes I’d come over to him and we’d go over the lines together.”

At first glance, it might seem unusual for a death metal band that has written songs such as “Remote Tumour Seeker” to appear on an Apple television project. Bands that play the more abrasive subgenres of heavy metal music tend to operate outside mainstream pop culture, but Archspire’s “See” cameo was hardly the first time that extreme metal music has infiltrated big-name television shows.

The “Friends” writing staff clearly had a headbanger or two on the team, as one of its episodes featured two references to the band Carcass. More recently, Pig Destroyer’s “The Diplomat” was extensively featured in a suitably over-the-top rat-killing spree on sitcom “Workaholics.” Of course, there’s also “Metalocalypse,” Adult Swim’s metal-themed comedy that paved the way for Dethklok, a real-world metal band that released a trilogy of well-received albums.

As for “See,” Peter sand Archspire drummer Spencer Prewett were featured in a brief cameo during Momoa’s war cry scene, but the duo wasn’t the only metal reference in the show’s pilot: The episode also introduced antagonist Tamacti Jun, who hunts down the show’s heroes. Jun’s title is Witchfinder General, which was also the name of an influential English heavy metal band.

Whether Momoa pushed for that reference is unknown — the actor was unavailable for comment — but he has made his affection for heavy metal music abundantly clear in prior interviews. Momoa told Metal Hammer last year that his “Aquaman” performance was inspired by songs from Black Sabbath, Metallica and Tool, while his work in 2011’s “Conan the Barbarian” drew on themes from Pantera. It’s not just talk, as Momoa has been spotted at various metal concerts in recent years, including a Slayer gig.

Peters noted that although working on “See” differed from performing during a metal show in a few ways, such as working with natural light instead of having artificial lights blasting out in a dark concert hall, there was nonetheless some overlap between the experiences.

“Already having the background experience of being in front of cameras while playing and having to have high energy during go time helped us out with being on screen,” Peters said. “Being on a big-budget TV set was a trip, and Jason putting us in speaks to the creative side of what he does. He has this crazy reputation and status, but he’s just a fun metal dude.”

“See” is streaming on Apple TV+. Archspire’s last album, “Relentless Mutation,” released in 2017 and the band is gearing up for a European tour.

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