A new documentary will pull back the curtain on the New York music mogul who set Metallica, White Zombie and other rock legends on their path to stardom.

HuffPost got a sneak peek at “Who the F**k Is That Guy?,” which hits theaters July 21, with the exclusive snippet above. The film traces the “tender, loving and sometimes self-destructive” life of former Elektra Records A&R executive Michael Alago from his Brooklyn origins to the peak of his career in the music business.

As seen in the clip, Alago, who is gay, doesn’t shy away from discussing his sexuality in the documentary. Being openly queer in the 1980s and ’90s was, of course, challenging for anyone working in the entertainment business. Still, Alago said his position afforded him a unique advantage. “Those young people, who you may have thought were homophobic, had to kind of put up with me ... because I was the person they would come to for the record deal,” he said. “They may have not met another gay person in their whole life. They would maybe leave my office with a different perspective of what ‘gay’ meant.”

Independent filmmaker Drew Stone, who raised money for the documentary through a Kickstarter campaign, can trace his interest in Alago’s career back to the ’80s. “It seemed as if every time I would go out to see music I would just keep seeing the same guy over and over again,” he told HuffPost. “After I met [Alago] and got to know him, it struck me that he had a uniquely interesting story ... It was a paradox I wanted to capture with the New York City aesthetic that influenced my life and millions of others.”

While heavy metal is not traditionally associated with queer culture, Stone said he found Alago’s “passion for aggressive-sounding music and his tenacious belief that some of these bands could go mainstream” inspiring. “He went with his heart and the love of the genre,” he said. “He proves that color, age, religion, ethnicity, sexual preference or any other categorization is totally immaterial to a fan of music. And he took the notion of being a fan to a level that has literally changed the music industry and how we listen to music.”

“Who the F**k Is That Guy?” hits theaters July 21, and will be available on demand and on iTunes July 25. Head here for more details.

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