Two Saturdays ago, three of Jim Roppo’s kids fired up KPop Demon Hunters during its opening weekend on Netflix, unaware that their dad, the Chairman/CEO of Republic Records, had anything to do with the movie or its soundtrack. Then, they watched it again. And again.

“My kids watched this movie three-and-a-half times in 24 hours,” Roppo tells Billboard of his 12-year-old, 13-year-old and 15-year-old children. And the next day, they started blasting the songs from the soundtrack. 

Roppo noted this behavior from “my own little home test-market group,” he says with a laugh, while also seeing how well KPop Demon Hunters was performing on Netflix, and the eyebrow-raising early streaming numbers from the soundtrack. Before the end of the weekend, “I started ringing all the alarms across the company, with all of our partners and teams,” recalls Roppo — what once had piqued the interest of his family was quickly becoming a global smash.

Since that opening weekend, millions of new viewers have watched KPop Demon Hunters, an animated musical about a fictional K-pop girl group, HUNTR/X, who secretly slay demon spirits when they’re not dazzling arena audiences. Two and a half weeks after the film was released on June 20, KPop Demon Hunters remains atop Netflix’s global top 10 movies list. And its soundtrack, which was released simultaneously, has surged higher on the Billboard 200, debuting at No. 8 and moving up to No. 3 in its second week, with 62,000 equivalent album units — a 97% increase from Week 1 to Week 2, according to Luminate.

When a soundtrack to an animated musical displays that type of growth, the culprit is usually a standout song or two — think “Let It Go” from Frozen. But KPop Demon Hunters is a phenomenon more reminiscent of 2021’s Hot 100-blanketing Encanto soundtrack, with seven songs from the soundtrack appearing on this week’s chart, led by the HUNTR/X anthem “Golden” at No. 23 and “Your Idol,” from their villainous boy band counterpart Saja Boys, at No. 31. Both songs have hovered near the top of daily U.S. and global streaming listings for days, but so have HUNTR/X’s hammering opener “How It’s Done,” the sticky-sweet boy band song “Soda Pop” and the pivotal ballad “What It Sounds Like,” all of which are currently in the top 11 of Spotify’s Daily Top Songs USA chart.

“It’s seven or eight songs deep — not just in America, and not just on one platform,” Roppo says of the set’s bench depth, also nodding to the strength of the two songs from K-pop superstars TWICE that appear on the soundtrack. “There’s no one who could tell you they predicted this.” 

That includes Ian Eisendrath, the film’s executive music producer. “I’ve always believed in the songs, and thought they would pop,” Eisendrath says, “but not like this.”

Eisendrath says that the music for the Sony Pictures Animation and Netflix film was developed over a three-year period, after being approached by Sony Motion Pictures Group’s music president Spring Aspers for the project. A veteran music director for film, TV and theater — with credits ranging from Disney’s recent Snow White remake to Broadway’s Come From Away — Eisendrath says that he was already a big K-pop fan, and felt like the “high-drama” music would naturally translate to an animated musical.

“It just felt so cinematic, so big,” he says. “The production is immense, intense and multi-layered, and that’s the kind of sound you want in a film.”

He worked closely with film co-directors Maggie Kang and Chris Appelhans — and several K-pop songwriters and musicians — to capture that gravity in the film’s various songs. Instead of functioning as the vision of a lone creative steward a la Alan Menken or Lin-Manuel Miranda, the KPop Demon Hunters soundtrack was assembled by a sprawling team of pop and K-pop studio experts — including The Black Label’s Teddy Park, 24, IDO, Jenna Andrews and Stephen Kirk — and vocal talents behind HUNTR/X (EJAE, Audrey Nuna, REI AMI) and Saja Boys (Andrew Choi, Danny Chung, Kevin Woo, samUIL Lee and Neckwav).

Across all of the musical players, the goal was the same: create K-pop songs that could work within the Demon Hunters narrative, and stand on their own outside of the story. “The songs were always functioning in both aspects,” Eisendrath explains, “as truly relevant K-pop songs, created by K-pop makers, that add to the overall narrative within the film, and as singles that are just universal pop songs.”

As the film and its music were being finalized, Republic Records was made aware of the project roughly a year ago, according to Roppo, thanks to Savan Kotecha, the veteran pop producer-songwriter (One Direction, Ariana Grande) now serving as the head of the newly formed label Visva Records. Sony Pictures’ Aspers originally brought KPop Demon Hunters to Visva, and Kotecha looped in Republic to partner on the soundtrack. “The vision behind the film and the uniqueness of the music felt electric from day one,” Kotecha says in a statement.

Meanwhile, TWICE was looped into the project thanks to Republic’s partnership with JYP Entertainment Corporation on the best-selling K-pop girl group’s studio output. In addition to TWICE’s previously released song “Strategy” appearing on the soundtrack, the group recorded their own version of the HUNTR/X diss song “Takedown,” and their group moniker appears in the film multiple times. “It meant a lot to all of us, says Eisendrath, “when they were willing to sign on and sing one of these songs — that felt like such an authentication of what we were doing.”

Upon the film’s June 20 release, Roppo says that the soundtrack’s cross-platform activity reminded him of Encanto becoming a home-video sensation during the pandemic. As such, the entire Republic promotional apparatus sprang into action. “We’ve built a machine to not only detect these early signals, but maximize opportunities very, very quickly,” he says.

Following the soundtrack’s second-week streaming explosion, Republic hustled to have “Golden” impact top 40 radio stations on Tuesday (July 8), as the song “that we feel has the most mainstream pop opportunity and appeal,” says Roppo. Multiple physical versions of the soundtrack are now available for pre-order, as is a 7-inch single featuring both versions of “Takedown” that ships later this week. And Roppo says that the team is discussing potential remixes of “Golden,” with some “A-list remixers” in play for a new version of the soundtrack’s biggest hit so far.

The summer of KPop Demon Hunters is just getting started, considering the global enormity of Netflix — which has an estimated 300 million viewers — and the fact that, unlike viral synchs from Stranger Things and Wednesday in recent years, the music appears throughout a 100-minute family film instead of showing up multiple episodes into an adult-leaning series. Yet Roppo says that some of the most encouraging internal data points he’s seen about the film is its viewership in the 18-to-44 demographic — as well as its appeal with viewers who did not previously watch any K-pop content on the platform.

“It has crossed the rubicon globally,” says Roppo. “This is not a K-pop phenomenon. Now, it’s a pop culture phenomenon.”