Probably the most powerful – and certainly the most emotional – moment in the new Big Star documentary arrives about three-quarters of the way in, as Chris Bell’s siblings remember his death at the age of 27. “I feel almost guilty sometimes talking about the music because it wasn’t my thing,” says Bell’s middle-aged sister, Sara. “I can’t help it; I almost resent it because it makes me sad. I mean, I’m happy for him, but I…” As she starts sobbing, her older brother David completes her thought: “You’d rather have him than the music out there.”

As you learn in Nothing Can Hurt Me, Big Star’s lack of commercial success maybe wounded Bell more than his bandmates. Alongside frontman Alex Chilton, the singer, guitarist and songwriter was one of the architects of Big Star’s sound. Bell died in a car wreck in 1978 and never saw Big Star’s music attain the global, if still cult-like adoration it enjoys today, let alone the reunions that Chilton and drummer Jody Stephens led in the ‘90s and 2000s.

With Chilton and bassist Andy Hummel passing in 2010 (of a heart attack and cancer, respectively), fans shouldn’t be surprised that there’s a lot of grief in Nothing Can Hurt Me. “I think it’s OK to dwell on that,” says Stephens, Big Star’s lone surviving original member. “There are a lot of movies that focus on that and you feel good about that grief. It has an emotional depth to it. There are great light moments too.”

While fascinating and entertaining, Nothing Can Hurt Me is indeed a sad movie. It tells the story of how the band became an instant critical darling, after the release of their 1972 debut, #1 Record, and how the fact that this praise never translated into record sales set Bell adrift, emotionally.

It charts Bell and Chilton’s soul-searching and sometimes awkward musical experimentations in and outside of Big Star, and explains how across-the-board critical success, imploding distribution deals, the resulting dismal record sales, generations of fawning peers (R.E.M. and The Replacements among them) and snowballing word-of-mouth over the decades contributed to the group becoming one of America’s most treasured cult bands. The band’s lone claim to mainstream fame is writing (not does that) the song “In The Street,” which was used as the theme to That ‘70s Show.

That sort of success was akin to “winning the lottery,” says Stephens, who was 17 when the band formed at Memphis, Tenn.‘s Ardent Studios. "I was just glad to be there, to tell ya the truth. I had such a sense of belonging, and it’s a natural, necessary thing. Some guys find it in gangs, some in basketball teams, some join bands. It was such a rewarding feeling. Of course, I always wanted it to be like The Beatles, but all that seemed like a pie-in-the-sky type thing."

Despite the fact that preproduction and even shooting began before his death, Chilton is noticeably absent from the film. “He didn’t want to be involved and he didn’t want to be filmed onstage,” says director Drew DeNicola. “He didn’t really say why, just that it was ‘not the kind of thing I’m inclined to do.’”

An almost complete lack of archival footage made things more difficult for DeNicola and producers Danielle McCarthy and Olivia Mori (who also codirected). Only about 20 minutes of 16mm film of the band in their heyday exist. “We’d hear about Big Star performing on TV in New Orleans in 1971, and we’d set out on three, four, even six-year-long searches for potential footage, but we would never find it,” says DeNicola.

The filmmakers compensated with photos, newspaper and magazine clippings and interviews with Big Star and Ardent Music/Studios insiders, several of whom, like producer Jim Dickinson, have since passed. In one memorable scene, fans and future bandmates in The dB’s Will Rigby and Mitch Easter recount tracking down Bell at the Danver’s fast food restaurant, where he was working at the time.

Another touching clip finds Congressman Steve Cohen eloquently paying tribute to Chilton on the House floor, tearfully noting, “He is the embodiment of Memphis music – hard, different, independent, brilliant, beautiful. We’re lucky he came our way.”

“It’s like a life’s experience, watching this film,” says Stephens. "I don’t know what Alex would have thought. I’m pretty sure Chris Bell would have been incredibly proud of it, and would have been pleased with the documentation of his work, and having the spotlight on what he worked at so hard and so passionately, as Andy would have been.