American Valhalla is about to hit select theaters, revealing the story behind an undisclosed collaboration between Iggy Pop and Queens of the Stone Age frontman Josh Homme that became to Post Pop Depression.

Homme co-directed American Valhalla along with Andreas Neumann. The film follows the pair's relationship from Pop's initial text to Homme to the creation of the album and the resulting tour. Queens of the Stone Age guitarist Dan Fertita and Arctic Monkeys drummer Matt Helders, who play on Post Pop Depression, are also featured. Check for updated information on screenings.

Self-financed and recorded in secrecy in Rancho de la Luna studio in the Mojave Desert, Post Pop Depression came about after Homme, who grew up idolizing Iggy Pop, received that unexpected message from his hero. Pop's desire to collaborate was born of a sort of musical claustrophobia he felt following the Stooges' reunion.

“I became one of those singers whose career is a slave to his band,” Pop says in the film. “I wanted an emotional escape, so I decided I had to strike out on my own, live and on record, to see what I was worth."

Meanwhile, Josh Homme was blown away by the idea of connecting with Pop, after growing up on Repo Man. "When he texted me about recording together, I was just like [explosion],” Homme says. “You’re in the Stooges, I’m in Queens [of the Stone Age] – and those are heavy things. Just hearing his voice, I could barely concentrate.”

The film captures a growing bond between the musicians, as they wrote, recorded, rehearsed and began touring behind Post Pop Depression, even following them at their most vulnerable – as when they learned of David Bowie's sudden death.

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