“This is insane. I’m losing my mind,” AJ McLean told a sold-out crowd at Sphere Las Vegas on opening night of the Backstreet Boys’ Into the Millennium residency. “I’ve cried at least four times since we’ve been up here.”

McLean wasn’t the only band member overcome with emotion during Friday’s nostalgic, otherworldly trip down memory lane. Kevin Richardson became so choked up he couldn’t sing his verse of “The Perfect Fan,” while Brian Littrell cried next.

Nick Carter was meanwhile fighting tears before he even rose onstage for 1999’s anthem “Larger Than Life,” which had audience members seemingly dancing through space while dodging meteorites thanks to Sphere’s immersive visuals.

“As I was about to come up, I started breaking down and crying because it was so emotional and surreal,” Carter told THR in an exclusive interview. “We’ve been together so long and had so many ups and downs, so the fact we can still perform on any stage is amazing.

“We’d been rehearsing for two months and we’re perfectionists, so we’ve been hard on ourselves, and finally getting to that place where you’re about to be launched out of a lift onstage was very emotional.”

It’s not surprising emotions were running high. For Carter, Richardson, McLean, Littrell and Howie Dorough, 1999’s Millennium record catapulted them to startling fame and cemented the foundations of a 32-year career that has seen them tour the world, release 10 albums, earn Grammy nominations, release a documentary and build solo careers. 

Meanwhile for fans, Millennium ignited their first musical infatuation or concert experience – or the tour they forever regretted missing. 

I was 17 in New Zealand when I helped launch a petition to bring the Into the Millennium Tour Down Under. Two decades later, I was mesmerized as the heartthrobs soared high above the stage on their DNA World Tour, sparking flashbacks to when they rode hoverboards through the air during Into the Millennium. “This is it,” I thought. “This is the closest I’ll ever get to seeing Into the Millennium.” 

Then came Millennium 2.0. 

An idea hatched eight years ago, Carter says the band hoped to transport fans back to simpler times.

“There was no social media and technology wasn’t as advanced,” says Carter. “People had to go to concerts to watch shows and we had to deliver. The Millennium tour was progressive. We were taking risks and facing the challenges of doing a production in-the-round and flying on surfboards.

“There were times we’d get stuck in the audience and things would break down because technology wasn’t what it is now. It was a simpler, great time and we’re bringing that back, so people can relive great music and feel like kids again.”

Yet, the residency was never about re-creating the 123-stop tour.

“We didn’t want to redo Millennium,” show producer and director Baz Halpin told THR. “Sphere’s a unique venue and with Backstreet being the first pop show, we didn’t want to repeat the Millennium tour, but take elements and blend them in. It’s like, ‘What would a BSB Into the Millennium Tour be if it was done for the first time in 2025?’”

“We wanted to build a story around Millennium — give it a character, then let world-building from song-to-song transpire from that,” Halpin continued. “We’ve built a galaxy which incorporates things people will recognize, but it’s Spherified.”

One of those familiar elements is the spaceship setting from “Larger Than Life.” Another Millennium dance anthem, “It’s Gotta Be You,” followed the opener, before the quintet veered off Millennium to 1997’s “As Long as You Love Me,” by which point Sphere was a dancing sea of white, thanks to McLean requesting concertgoers don white like the album cover. 

Saluting the group’s iconic “I Want It That Way” video (filmed at LAX,) the airport theme’s dripping with ‘90s nostalgia, like a replica of MTV’s Total Request Live set with cardboard cutouts of BSB and host Carson Daly. Fans can also stop by the BSB Mail Centre to post fan mail or see memorabilia including MTV VMA awards, handwritten set lists and costuming.

Stopping by on Thursday, BSB were said to be so excited by the experience they offered up more memorabilia, before eagerly recording and broadcasting boarding announcements.

From here, the walkway from The Venetian to Sphere feels like an airport air bridge (complete with a mass, post-show “I Want It That Way” singalong).

Along with such hits, the band delivered favorites like “Don’t Want You Back,” and “Get Another Boyfriend,” accompanied with slick dance moves care of longtime choreographers Rich and Tone Talauega. Heart-wrenching “Show Me the Meaning of Being Lonely,” meanwhile, was backdropped by smoky spirits performing interpretative dances. 

The set list was the first and most “critical” step, according to Dublin native Halpin, who carved out his career working with boy bands like Westlife, Boyzone and Blue. He’s since worked on The Eagles’ Sphere residency, UFC Noche and Taylor Swift’s Eras Tour.

Halpin recalls hearing about the “iconic” Into the Millennium tour, but never imagined he’d one day get a call from BSB manager Ron Laffitte about creating a Sphere version. He’s grateful the group quickly comprehended the “gravitas” of every creative decision.

“You can’t reverse when you’re creating in Sphere because it’s so technologically complicated,” Halpin said. “With every layer, you’re building on the foundation and it’s got to be absolutely right, so the next layer’s solid. If you pull a toothpick from the bottom, the whole thing topples.”

“The band caught on that we had to nail down songs and not deviate six months out otherwise all the work would fall apart. There’s no time to redo things like a normal tour. You can’t make another piece of content in three days — it takes three months.”

While the hits were a must, it was a medley of lesser-performed ballads that had fans hypnotized, like “Back to Your Heart,” “No One Else Comes Close to You” and “Spanish Eyes”. “This is my mom’s favorite song,” Dorough shared. “She’s here and 91!”

Moms were also the theme of “The Perfect Fan,” with photos of the band’s wives, kids and moms flashing across screens. “This song’s super-special to me,” Littrell explained. “I wrote it many moons ago and dedicate it to my mother.”

Fans were in tears as the group crooned haunting 2005 ballad“Siberia,” while screens showered virtual snow and displayed aged versions of BSB in a Mt. Rushmore-style visual.

They also performed 2025 single, “Hey,” which features on newly-released Millennium 2.0, alongside remastered versions of the original tracks, live recordings and B-sides like “If You Knew What I Knew.” 

Of course, it was the final act everyone was waiting for — airborne BSB. The “BSB Army” had long wondered if the hoverboards from the original tour would appear, with Dorough teasing an “adaptation” of such moves to THR in May. The singers instead rose on a spacecraft-style platform during “I Want It That Way.”

For Carter, it was the coolest moment of the production. “We’re raised into the air suspended with four cables,” says the musician, who has released solo album Love Life Tragedy alongside preparing for Sphere and will drop new single “Searchlight” on Thursday. “It’s secure, but also a little dangerous and just mind-boggling.”

Following debate over the best seats for the show, the 200s sections proved optimal for taking in 360-degree effects, while feeling eye-to-eye with BSB as they floated above the stage. However, general admission took visuals to another level as I frequently questioned if the ground or stage was moving while feeling sucked up into the screen.

“I’m going to need chiro after this,” one fan remarked, craning her neck. Other GA attendees wore compression socks, stretched mid-show and briefly left to pump breast milk — somewhat answering Halpin’s question of what an Into the Millennium Tour looks like in 2025.

GA was also where the party was at as “Everybody (Backstreet’s Back)” closed the show with robots performing the video’s iconic choreography onscreen.

By the time show two wrapped on Saturday, the quintet was in celebratory mode at The Venetian’s Voltaire, where Richardson, 53, led a singalong to Fugees hit “Killing Me Softly.” It’s rare the whole band attend afterparties, but it reflected the solid team effort behind Sphere.

Halpin stressed how each member’s input was imperative. “It’s like Inside Out, where they’re all different emotions and bring a unique character. Kevin questions everything. He needs to understand every detail to build the whole picture. Brian’s asking, ‘How is this decision impacting everything else we’re going to do?’ AJ’s all about, ‘How do we keep the crowd’s energy up?’”

“Howie wants to understand the emotion behind everything. Nick’s the canary in the coal mine. When we did tests, he was the one I’d look to to gauge reaction. You look to Nick to see how an audience member’s going to experience it.

“When you combine all those perspectives, it becomes cohesive and very Backstreet Boys. They know who they are and what their fans like. But they’re also risk-takers, who want to push boundaries.”

In doing so, Halpin believes Into the Millennium’s a game-changer for Sphere.

“We’re pushing the limits of what’s been done at Sphere because we came in with the experience of other shows,” he says. “Sphere was a newborn with U2, and with every artist that’s gone in since, it’s had another birthday and grown. Every band before has been a soundtrack to the visuals, but this show’s different. It’s the most ambitious show that’s been done in there.”