After watching the new documentary Turn It Around: The Story of East Bay Punk, I can’t help but think about a teenager named Jimmy Mahoney, who last year was called up on stage by Billie Joe Armstrong from Green Day for a dream opportunity: to play guitar with his favorite band in front of thousands of people.

The band does this for a fan routinely, almost every night on tour, but on this night at the Oracle Arena, after two songs, Billie Joe unexpectedly gave Mahoney his guitar to keep, covered in stickers from early-’90s East Bay punk bands like Monsula, Econochrist and Spitboy.

You have to wonder: Was the guitar intentionally decorated with those band’s stickers beforehand? As clues, perhaps, for its young new owner in a musical treasure hunt? Did Jimmy bring the guitar home and Google those bands, and discover the influence they had on his teenage heroes?

Turn It Around, a 158-minute documentary produced by members of Green Day which opens May 31, is that same idea in extended cinematic form. Released during Green Day’s current world tour of sold-out arenas, it’s their way of telling the world: We didn’t do this alone. The East Bay is special. Here’s where we came from.

It’s a job that tireless director Corbett Redford, 41, didn’t take lightly. “I know I’ve been tasked to represent a sacred history,” the musician, filmmaker and Pinole native says. “I spent four years of my life letting it consume me. But it had to be done right.”

Narrated by Iggy Pop and featuring commentary from 150 band members, zine editors, volunteers and more, Turn It Around is a massive, authoritative document of the scene around the Berkeley all-ages club 924 Gilman that would eventually change punk rock all over the world. Packed with previously unseen footage — Operation Ivy’s early rehearsals, Miranda July’s 1992 play staged at Gilman, unearthed images from photographer Murray Bowles’ vast archive — the film brings in perspective from observant outsiders like Bikini Kill’s Kathleen Hanna and Fugazi’s Ian MacKaye on down to less-celebrated contributors like the drummer of Sewer Trout and that one guy who got too drunk once in Eggplant’s backyard.

Because of this breadth and length, there’s no singular narrative driving Turn It Around, no easy-entry character study for a mainstream public. It’s unlikely the film will have the same crossover success as, say, Searching for Sugarman or Standing in the Shadows of Motown, or other looser documentaries that don’t let the truth get in the way of a good story.

But that’s why it’s definitive. As someone who spent his formative teenage years going to Gilman, volunteering there and yes, even sleeping at the club during the years in the film (which, full disclosure, I’m seen in for a split second), I can’t find much that it omits. For others who were there, and for the growing number of kids worldwide interested in the era, there’s value in this. Redford says he originally cut a five-hour version from 500 hours of footage before the final two-and-a-half-hour cut, and with any luck, that extra footage will surface as DVD extras or on streaming services after this theatrical run. Ask anyone involved in the punk scene at the time, and they’ll tell you that it’s impossible to boil it down to one simple story.

The film crew itself evinces a “by the punks, for the punks” philosophy: both Absolutely Zippo editor Robert Eggplant and drummer and booker Kamala Parks served on the production crew, and the titles and illustrations were hand-drawn by Cometbus editor Aaron Cometbus, Rancid’s Tim Armstrong and Operation Ivy’s Jesse Michaels. Before this, his first full-length film, Redford had mainly directed videos for his band, Bobby Joe Ebola and the Children Macnuggits.

That band name hints at the humor in the film, and also the idea, embraced by figures like Tales of Blarg editor Janelle Hessig (and bands like Stikky), that despite the East Bay punk scene’s impact, it isn’t to be taken too seriously. Turn it Around’s release during the current 50th anniversary bonanza for the Summer of Love is a curious study in contrasts on how to commemorate a musical moment.

“One thing we’re not trying to do is mystify that time,” Redford says, citing the Chicago punk documentary title You Weren’t There as an elitist idea he wanted to oppose. “We’re just trying to show how human or normal a lot of these larger-than-life figures were, how they did their best to try to make something good. We’re not saying, ‘This is the best scene ever.’ You know?”

That said, the film doesn’t lack in context. It opens with then-California governor Ronald Reagan ordering gas to be dropped on protesting students at People’s Park in Berkeley, soon moving to MaximumRockNRoll founder Tim Yohannon’s on-air argument about punk with rock promoter Bill Graham. Many cultural forces coalesced in the 1970s to guide Bay Area punk, and even Kirk Hammett from Metallica and Duff McKagan from Guns ‘N’ Roses attest to the notion of the 1980s San Francisco punk scene as the country’s strongest.

Berkeley was a bastard child of it all, a place where kids of hippies and college professors resisted trends. The film hits its stride with the founding of the Gilman Street Project, and its philosophical opposition to knuckleheaded thrash shows with drink minimums and violent pits. In fact, the pits at Gilman are decidedly silly: “geekcore” punks play leapfrog in a circle, or ride tricycles. The band Isocracy hauls in hundreds of pounds of garbage from dumpsters, and throws it on the crowd and themselves. Inexplicably, an odd trend emerges of stagediving into bushes, and an anthem for it is written.

Gilman goes through various changes, including an infiltration by skinheads (in an uplifting segment of the film, the geeks fight back), but a running theme is the folly of fame. Operation Ivy breaks up because they get too popular. Yohannon suddenly closes Gilman when he feels it’s achieved all it can. The insider nature of “THE LIST,” replete with “@:pit warnings” by veteran Steve Koepke, is lauded as a secret, pre-internet social network. When Gilman reopens, and Green Day starts packing in a more normal, preppy crowd than usually frequents the club, many diehards get nervous. By the film’s end, Green Day signs to a major label, a trenchant debate over what constitutes “punk” rages, Tim Yohannon passes away, and Gilman goes on to enjoy an influx — continuing to this day — of enthusiastic kids ready to start something new.

No punk scene is without its scandals, and Turn it Around conspicuously ignores them and other unsavory bits of lore: Jello Biafra getting his leg broken by crust punks; Sam McBride from Fang being convicted of killing his girlfriend; the Feederz throwing a dead dog into the crowd. (Readers can find these stories in Jack Boulware and Silke Tudor’s excellent oral history Gimme Something Better: The Profound, Progressive, and Occasionally Pointless History of Bay Area Punk.)

That’s intentional, Redford says, and ultimately, the film’s theme isn’t Do It Yourself so much as Do It Together. “The emergence of the Gilman Street Project is a pretty good example of the good things that can happen when people are nice to each other, when they decide to cooperate and build as opposed to destroy or backbite,” he says. “And again, our scene isn’t perfect, but I think that in the world today, places where outliers can converge are very important.”

That’s evident in the diverse alumni of Gilman’s scene. Queercore groups like Tribe 8 and Pansy Division; feminist bands Spitboy and the Yeastie Girlz; black performers like the Beatnigs’ Michael Franti or Special Forces’ Orlando all weigh in. Stylistically, too, the music ranges from the Beatles-inspired harmonies of Sweet Baby to the nascent emo of Jawbreaker and the hardcore nihilism of Christ on Parade. Billie Joe, singer for one of the poppiest bands on the planet, saves his strongest words of enthusiasm for apocalyptic doom-punk overlords Neurosis.

And that may be the underpinning lesson of Turn it Around: that it’s about something bigger than music.

“East Bay punk to me was always just a thoughtful, heartfelt, intellectual kind of thing,” says Redford. “And it taught me that punk, as opposed to just a costume or spitting on authority, is about potentially being a better citizen of the world. You know?”

‘Turn it Around: The Story of East Bay Punk’ premieres on Wednesday, May 31, at the Alamo Drafthouse New Mission Theater in San Francisco as part of SF DocFest. A Q&A with the director, an afterparty, and others from the cast and crew are all part of the premiere; details here. A national theatrical run begins June 2. For more details and photos from the film, see here.