Oh my god, they’re back again.

For nearly a month during the waning days of summer, the town of Butte, Montana—pop. 34,000, birthplace of Evel Knievel, and one of America’s oldest rough-and-tumble boomtowns—played host to a liquid dream larger than life. A bloody post-apocalyptic dream filled with zombies, cowboys, three Backstreet Boys, a 98 Degree, a few ‘NSYNCers, and not one, but four members of O-Town.

Over the course of three weeks the Dead 7 shoot saw dozens of totally ’90s superstars, cast, and crew descend on the sleepy Montana town, invading bars, the local dance club, and Butte’s own Buffalo Wild Wings.

It brought hordes of the undead into town to rip flesh and famous people apart, including a carful of super fans who’d driven all the way from California just to play zombie extras alongside their favorite tweenhood dreamboats.

And on at least one occasion it led to a historic moment in which members of several boy bands shared the same karaoke stage, singing along to the classic cut “I Want It That Way” as some onlookers delighted and other nonplussed locals reportedly stared into their beers, unaware of the once-in-a-lifetime magic that was transpiring before their very eyes.

By the time I arrived on an unforgivingly cold afternoon to the set of Dead 7, Nick Carter and AJ McLean of The Backstreet Boys were preparing to play a scene as Dead 7’s cowboy hero and Droog-like villain. Nearby loomed the serene Our Lady of the Rockies, Butte’s iconic mountaintop monument to womankind. She watched over as the boy-band zombie Western was filmed on the side of a mountain, 8,000 feet above sea level.

In the middle of a shot, a flash hailstorm of Dippin’ Dots-sized flurries began pouring down on the crew. The three-week shoot had seen blinding sun, 90-degree heat, rain, sleet, and snow hit an array of gorgeous sets around Butte, but even on the penultimate day of a challenging 18-day shoot nobody was complaining.

As the camera rolled, the Dippin’ Dots pounded down harder. Dead 7’s director, Danny Roew, called for a break to wait out the weather. Everyone headed toward the visitors’ center that had been transformed into a makeshift indoor base camp, complete with a circle of camping tents—the indie movie answer to talent trailers.

The film’s leading lady, TV host and actress Carrie Keagan, pulled out her phone and started Periscoping the madness to her 406,000 Twitter followers. Someone sang the unofficial Dead 7 theme song in pitch-perfect tune in the style of The Weeknd, as a snowball fight erupted: “I can’t feel my face when I’m in Butte…”

Welcome to boy-band movie summer camp.

Montana’s boy-band zombie apocalypse began as the brainchild of one-fifth of The Backstreet Boys. After spending seven years developing his own idea for a zombie Western called Dead 7, Nick Carter, the youngest BSBer, landed backing from The Asylum, the schlockmeisters behind Sharknado. He’d already dabbled in film and TV and become a reality-television star, and this would be Carter’s first starring vehicle. But Dead 7 needed more pop power.

Set in the distant post-apocalyptic future after a mysterious zombie outbreak has decimated the population and knocked out all means of 21st-century technology, Dead 7 opens on a society that’s regressed to an Old West existence. Carter stars as a stoic cowboy named Jack who’s called home when a villainess (Debra Wilson, who invented her own language to play Apocolypta) starts amassing an undead army out of the Rocky Mountain copper mines.

“There was this idea of having a cast of boy banders, maybe Shaquille O’Neal, and some traditional actors, and making a crazy hybrid-collage of a movie,” explained Carter, who executive-produced and co-wrote the tongue-in-cheek genre mash-up inspired by a childhood watching Clint Eastwood’s Man With No Name trilogy and horror classics like Night of the Living Dead.

Shaq never returned Carter’s call. But ‘NSYNC’s Joey Fatone did. “One of the characters was called Whiskey Joe, and I thought about Joey Fatone—for some reason I thought he’d be awesome to play the part,” said Carter.

Fatone was cast as an alcoholic brawler who, like Jackie Chan’s classic Drunken Master, channels his boozy ways into a surprisingly graceful inebriated fighting style in one of Dead 7’s genre-bending action scenes.

“He’s Beetlejuice meets Captain Jack Sparrow,” offered Fatone with a laugh. With several indie films to his name—including the upcoming My Big Fat Greek Wedding 2—the former ‘NSYNCer has the deepest screen résumé of the cast. “I think people will be pleasantly surprised. We’re taking it seriously. That doesn’t mean that the actual movie is serious. I mean, come on—we’re fighting zombies, for cryin’ out loud.”

After Fatone, more boy banders flocked to Dead 7. Carter’s BSB bandmate AJ McLean came aboard early to play Johnny Vermillion, a Clockwork Orange-inspired goth-punk psycho zombie-wrangler who wears clown makeup and keeps the severed fingers of his victims in a holster.

Aside from developing his character’s sociopathic quirks and costume, McLean cultivated a gleeful cackle for his character so piercing it floated through the Montana air throughout filming.

“Once all the makeup was on, the voice came out and then the laugh happened,” said McLean, who grew up acting and doing theater before his boy-band destiny came calling. “I didn’t want it to be too close to any version of The Joker, I didn’t want it to be too geeky… It needed to be sinister, the kind of laugh that makes you cringe.”

Like the Avengers of ’90s pop, the cast of Dead 7 was assembled like a Now That’s What I Call Music film fantasy. Jeff Timmons of 98 Degrees gives off a muscular All-American charisma in his film debut as Billy, Jack’s estranged brother who must begrudgingly reunite with him to help save humanity. Complicating their brotherly love is Daisy (Keagan), Jack’s gun-toting ex-flame, who is now engaged to Billy.

“I refer to it as our Legends of the Fall story,” Keagan teased during a break in filming, shortly after shooting a scene in which her Daisy is ambushed by McLean’s maniacal underboss in a rusted out train yard. “Jack had his Brad Pitt moment and just had to go.” Not that anyone has much time for love triangles. Daisy’s a zombie-blasting machine who greets the undead packing a pair of pistols and a knife.

Also along for the adventure in supporting roles and cameos are a who’s who of ’90s pop: BSB’s Howie Dorough, ‘NSYNC’s Chris Kirkpatrick, Jacob Underwood, Trevor Penick, Dan Miller, and Erik-Michael Estrada of O-Town, Delious Kennedy of All-4-One, Lauren Carter, Seth “Shifty Shellshock” Binzer of Crazy Town, Art Alexakis of Everclear, Tommy McCarthy from No Authority, and “Rico Suave” singer Gerardo. R&B elder statesman Jon Secada, naturally, plays the town sheriff.

Sheriff Jon Secada. Be still, my ’90s heart.

As it happens, the stars of Dead 7 are members of a very small club of performers who lived through the boom and bust of their ’90s-’00s pop fame. The guys from Backstreet, 98 Degrees, ‘NSYNC, and O-Town watched from the inside as the boy-band bubble burst for each group, one by one.

Luckily for icons of yesteryear, pop culture tends to repeat in two-decade cycles. Like clockwork, as soon as the ’90s became the new ’80s America hungered for more Backstreet. In 2011 the boys of BSB teamed up with their forebears, the New Kids On The Block (all now over 40), to form the world’s first boy-band supergroup, NKOTBSB, touring four continents and scoring $40 million in ticket sales.

“We have the best fans in the entire world,” McLean said, relaxing momentarily in a faux church pew on the last day of Dead 7’s shoot. The past few years have seen not only New Kids and Backstreet bounce back, but also the re-formation of O-Town, the last of the boy bands. All have since recorded and released new music—largely without the kind of major label support they had when they first emerged as corporately packaged products.

“We’re one of the last bands like us still here, still moving forward,” said McLean. “With the new boy-band resurgence—New Kids, O-Town, us—a lot of the guys after taking a long hiatus are picking back up. We’re 35-plus and still doing it, still dancing and having a blast, and when we get out there it’s like we’re 19 again.”

Backstreet will likely continue their 20th anniversary In A World Like This tour, McLean says, and have discussed reuniting with NKOTBSB again. Around the Dead 7 set, there’s been enthusiastic talk of the cast recording a soundtrack filled with new original tracks. (Just as excited is chatter of a sequel—yes, already—that could bring everyone back.) Without a record label behind them, groups like Backstreet are, in many ways, more in control of their own destiny than they ever were before.

“We are our own label now,” said McLean, who’s prepping to release a new solo album. “So to know that we can still sell millions of records, tour arenas and stadiums with no other support than just our core fan base, and pulling in new fans…”

“It’s a double-edged sword,” he continued. “If you want to be on radio, you should have a label because to be on the radio is not cheap. You’re looking at three to four figures if you really want to get enough spins and beat people in the head with your song. Aside from that you can do a distribution deal or a simple licensing deal [without a label].”

Timmons knows that hustle firsthand. After 98 Degrees, “I couldn’t get a record deal for a long time,” he admitted. “It wasn’t that great of an album. I produced it myself but I was pretty new at that.”

Instead, he picked up the phone with an enterprising plan to land on-air play. “I ended up working the record myself hustling radio under two fake names, Ed Furby and Fred Smalls, and that’s how I got the record on radio every week,” he laughed.

McLean’s going a slightly more traditional indie route with the first single off of his upcoming album. (Carter, too, has a new album coming out next month.) “I’m taking label meetings but if it doesn’t happen, I know I’m fine,” he said. “I know I can just do it on my own—do distribution deals in different regions around the world. Fortunately, I’m part of a group that has global, worldwide success. But if the U.S. is fixated solely on Maroon 5 and Taylor Swift and Rihanna, that’s fine. I’ve got the rest of the world I can go tour.”

Still, “it would be nice to be on radio,” he smiles. “We haven’t been on radio since ‘Never Gone’ with the Incomplete record, and it’s not because our friends that are DJs at Top 40 stations don’t still love us, it’s because it’s all ClearChannel and their boss has to answer to another boss. There are so many channels of power that unless you’re the hot thing, nobody really cares.”

It’s not just the music industry that gave the boy banders the cold shoulder. Many of these onetime princes of pop say they tried their hand at acting years ago only to find Hollywood’s doors closed to them, ironically enough, because they were in boy bands.

“Dead 7 gives them the platform they’ve never had before to act in a movie,” said Roew of his sprawling cast. “As strange as it sounds and as established as they are, these guys are all hungry actors who want stuff for their reel.”

“I couldn’t even tell you how many auditions I’ve been on in Hollywood,” said Carter, who conceived of Dead 7 as a vehicle for himself after years of frustration trying to parlay his music career into acting.

“There are so many different things to factor in. Number one, you’re in a boy band so you’re already typecast. Two, you’re on tour all the time, so do you have time to film a movie? In the movie business, you’re only as good as what you offer. That’s how they look at you.”

“That’s why all these people wanted to jump onboard, and that’s why I wanted to give them that opportunity,” said Carter. “Because they deserve that opportunity. They’re hard workers, they love acting. Actors want to be musicians; musicians want to be actors. But unfortunately, nobody wants to take a chance with a musician. I was happy to open that door if they wanted it, especially in a genre that we all love.”

Tall and blond, Carter cuts an archetypal figure as a gunslinger racing through the zombie-infested future. He also shares a storyline with offscreen wife Lauren Kitt Carter, who plays a nomad warrioress named Sirene. Halfway through the Dead 7 shoot, ABC’s Dancing With the Stars announced that Carter will compete on its 21st season, and a network camera crew sped to Montana to shoot promos between scenes.

“It’s been crazy, but I’m at a place in my life right now where it’s taken a long time to get back, for me to get to where I am right now,” Carter said. “I had a rough path to come to the life that I made for myself when it comes to partying, my mishaps, and all these things I did in the past; I made it difficult for myself. So what I’ve done for the past seven or eight years was remember to work on what I can, work on what I want to do, and focus on being professional.”

“Seven years ago when I first started writing screenplays I said, I can’t do this cattle call any more in L.A.,” said Carter. “I love acting, but I can’t do this any more so I’m going to write my own screenplay. Now seven years later it’s come to fruition. It’s a great feeling. I’ve been taking all the opportunities that are thrown at me and using them in a positive way.”

Several boy band vets started writing their own scripted projects as a means of breaking into acting. Timmons, who lives in Las Vegas where he emceed the live Chippendales show (but stayed fully clothed), spun that gig off into his own male stripper reality series for E! He has other projects in his back pocket, including a show based on the boy band he had before he joined 98 Degrees.

Estrada, the youngest boy band veteran in the cast, remembers crossing paths with Carter in audition rooms a decade ago when the O-Towner and the Backstreet Boy both moved from Florida to Los Angeles chasing Hollywood dreams. O-Town had just disbanded, and Estrada had eyes on acting.

“We’d go out for a lot of the same reads and were getting turned down equally, because we were typecast,” he recalled as we sat on a wooden walkway inside a historic mining museum. “We met up at a bar talking about how L.A. life was so hard.”

“It’s so hard for guys who come from what we came from, shortly after we came out of it. People had a hard time thinking, ‘These guys aren’t legitimate performers, these guys aren’t legitimate actors, boy bands have run their course, boy bands are over, we’re looking elsewhere for fresh faces.’ It was troublesome because I think both of us were ready to take it on.”

At one point, both boy banders even screen-tested for roles in Coach Carter, he revealed. “It didn’t come to fruition and that’s fine,” he said with a smile. “Everything happens the way it’s supposed to.”

Estrada had started his music career not only as part of O-Town (like Backstreet and ‘NSYNC, a product of the Lou Perlman machine) but as an early-generation reality-TV star alongside his O-Town mates on MTV’s Making the Band, a three-season experience he calls “therapeutic.”

“It was uncharted territory. It was like Star Trek, we were venturing into galaxies unknown and winging it,” he said. “I learned a valuable lesson early on—the first season, I didn’t know what it was, or what reality TV was, or what they wanted to get, so I didn’t give them enough of me. I think that’s the biggest flaw you can have in reality TV, to be guarded. You have to allow yourself to be open.”

Like his peers, Estrada responded to the challenges of post-boy band life by changing course. He found his way to independent film, writing screenplays and short stories while keeping a hand in music. And after a long hiatus, O-Town reunited in 2013 minus member Ashley Parker Angel and released their third album.

“We’re all adults now and we all bring something different to the table from our experiences, whereas when we were in the band we were like 20 years old and didn’t know our foot from our ass in terms of our identities,” Estrada mused. “You put five individuals into one group and I think it’s actually tougher to find your identity, because you’re constantly comparing yourself to everyone in the band.”

“It’s great that we took time away and still have sound mind. We survived that time. Then could come back and consciously do it for all the right reasons, not all the wrong reasons.“

Inside an RV filled with monitors and laptops, Dead 7’s editor scrolls through footage from the past 18 days.

Fatone’s drunken master bar fight is a crowd-pleaser, as are scenes of McLean gobbling up the scenery as Dead 7’s delightfully off-kilter villain. Aerial footage caught by a 7D affixed to a drone soars above and around the mountain set making the massive Our Lady of the Rockies statue look like Rio’s Jesus figure, overlooking the valley below.

Outside, the sunlight is fading. Estrada, his hair in a samurai’s topknot, is still wearing his costume, two heavy katana blades strapped across his back. Cast as a ninja-esque character named Komodo, Estrada had only four days for weapons training before filming. He demonstrates his moves, fluid and studied.

Earlier in the day he had officially picture-wrapped. “It’s emotional,” he admitted, turning to flash a brief smile.

Later, Fatone would tell me how the Dead 7 shoot brought everyone together. Timmons had never been on the set of a film before, let alone starred in one, and would hang around even when he wasn’t shooting, a giant grin on his face.

The cast and crew were known to gather in Fatone’s room late at night playing games. “I honestly never thought that me and Howie would ever hang out, but we had a great time and laughed and bullshitted the whole time,” he said.

As for the film itself, “it’s like every woman’s wet dream. Even Carrie [Keagan]’s hanging with the boys,” he laughed, promising one thing: Dead 7 will be the best boy-band movie ever made. (That includes two curious artifacts lost to pop music history: Longshot and On The Line.)

A second unit picks up shots of a severed head rolling along the ground just so while director Roew, DP Gustavo Petersen, and two dozen extras and crew members have descended into the mouth of the Orphan Girl copper mine.

They’re perfecting one last a scene in which Billy, Jack, and Sirene quietly sneak through a darkly lit mineshaft thick with zombies. Later in the film, they narrowly escape the undead and burst out into sunlight, bolting the doors as hungry hands reach out at them through the cracks and crevices, groping at them.

The question is, will audiences embrace Dead 7 and its earnestly self-aware cast of boy-band royalty, which SyFy Channel will debut next spring?

“I mean, think about it—we’re boy-band guys trying to save the world,” Carter later mused. “That’s funny. You can’t stop that from being what it is. I just decided that I was going to create my own lane. I’m going to do my own thing, and if it works, it works. If it doesn’t, who cares? I had fun doing it.”

“And, who knows,” he said with a laugh. “Maybe it will turn into an awesome B-movie that people will remember.”