There’s a saying: Everything old is new again. Trot, a traditional Korean pop genre, is en vogue. Recently, a fresh new group ushered in the newtro (a clash of “new” and “retro”) renaissance of pristine, vintage pop that made K-pop feel contemporary by subtracting from it, leaning on innocent appeals with less bombast and vocal grandstanding. Like their predecessors, AND2BLE (pronounced “And-Double”) is trying to take fans on a blast to the past, back to third-generation K-pop.

For AND2BLE, though, the trip backward is also a way forward. The five members have already lived through one version of themselves: Zhang Hao, Ricky, Kim Gyuvin and Han Yujin debuted in ZEROBASEONE after joining the survival show Boys Planet, while Yoo Seungeon, who finished 16th on the show, went on to debut in EVNNE. When ZEROBASEONE’s project contract concluded, the four YH Entertainment members left the group; Seungeon likewise departed EVNNE. All five have now regrouped under YH as AND2BLE.

Their debut, Sequence 01: Curiosity, is a five-track, roughly 14-minute exercise that recreates the style of K-pop’s past. It remembers a time when a K-pop boy group could be expected to sound expensive, vocally athletic, and indulgently overdramatic without neo-futuristic theater. Plus, AND2BLE are flexing their historical know-how, investing heavily in the voice.

Seungeon brings clarity and high-register power; Hao supplies a steadier, warmer counterweight. Ricky’s softer, R&B-leaning delivery changes the texture of a song, while Gyuvin and Yujin fill out the middle with smoother, more understated tones. The pleasure is in the handoff.

TAEHWAN KIM

“Curious,” the title track, makes that nostalgia instantly legible. Its synth-pop and future-house architecture is all propulsion: a thick bass foundation, hard-edged EDM percussion, and an anthemic hook that’s designed for music show stages anchored by the rallying of Seungeon and Hao’s vocal ping-ponging. It is, in other words, unabashedly K-pop in the old sense. The track is also a reclamation of the members’ careers. “Curious” (co-writing participation by Hao and Ricky) confronts the instability of a new beginning rather than retreating from it (“Start anew, with no limits”). Still, the members are hardly new to being watched. They have already passed through the strange acceleration of survival-show K-pop, already inhabited identities that belonged to other groups, already acquired audiences who’ve stayed with built-in barometers of expectations.

“Aura” is where the rebirth process promised in “Curious” becomes crystalline. It is less interested in the title track’s muscularity, opening instead into a gauzier pop-R&B landscape of synths and hushed vocals. The song’s central conceit—an attraction born of ineffable personal magnetism—is buoyed by a coyness poignant enough to create negative space. The vocal texture itself is part of the flirtation: “I’ll show you piece by piece, everything / You’ve never seen a brand new era / All I’ve got, aura / I can make it alright for ya.”

“Sugar Rush” is brighter, boyish, and immediately digestible, built around an addictive bubblegum groove. It is the record’s most pleasurable song, allowing the boys to flex their dexterity. Where “Curious” foregrounds ambition and “Aura” cultivates mystique, “Sugar Rush” is simply interested in momentum. Its attraction is physical rather than philosophical: the rush of wanting something and not particularly caring whether you should.

A debut this concerned with re-fortifying identity could easily become portentous, every song straining to explain what AND2BLE means. “Sugar Rush” refuses the assignment. It is candy rather than manifesto. And because the production leans into the sleek dance-pop vocabulary associated with the groups these members came from, it also functions as a reminder that reinvention does not require total repudiation. Sometimes the new identity begins with admitting what already works.

Then comes “Bed,” the album’s strongest argument for its vocal architecture. The track, a metaphorical frame for their dreams, begins with restraint from Zhang Hao before expanding into pop-R&B, moving into its chorus with a tenderness apt for boys who have been through the psychological warfare trenches of reality television (“Frame to contain your dreams / Baby you can take my hand”).

“Happy &” closes the album by changing the emotional register again. Its alternative-pop foundation is warmer and more communal, with an uncomplicated singalong quality. Hao and Gyuvin’s songwriting contributions stand out, as the song’s ethos is ultimately about the meaning of arriving somewhere together.

That makes the “sequencing” almost mischievously neat. “Curious” asks what happens when you step into something new. “Aura” asks what makes you compelling once you’re there. “Sugar Rush” gives in to the pleasure of it. “Bed” strips away some of the spectacle. And “Happy &” turns outward, toward the people who make the new beginning worthwhile.

TAEHWAN KIM

The album’s treatise, then, isn’t nostalgia. It is independence. In an era when K-pop has become increasingly adept at abstraction—concepts, lore, visual worlds, genre hybrids, euphemisms—there is something almost radical about returning to the voice and narrative storytelling as scripture.

AND2BLE’s own participation in the songwriting reinforces that impulse. Hao and Ricky’s writing contributions to “Curious,” Ricky’s to “Aura,” and Hao and Gyuvin’s to “Happy &” don’t transform the album into an auteur statement; most of the production remains collaborative and outsourced, as is standard for idol pop.

But the credits puncture the idea that these members are simply performers executing songs handed to them, or that novelty means sounding unprecedented. Sequence 01: Curiosity makes a case for independence through inheritance. AND2BLE seem less interested in escaping K-pop’s history than in selecting a particular part of it and deciding that it belongs to them.

The result is not a radical debut. There are moments when the record’s affection for third-generation conventions borders on reverence, and its brevity means that several ideas disappear just as they begin to acquire definition. But the album’s compactness is also its strength. Sequence 01 doesn’t pretend that AND2BLE have already solved the question of who they are, and it doesn’t have to be, as its title suggests. Hint, hint, nudge, nudge, there’s more to come.

TAEHWAN KIM