Peter Bjorn and John, more commonly known for their soft indie-pop sound, blew our minds at Irving Plaza. The Swedish indie trio arrived for the New York stop of their Writer’s Block Anniversary Tour, bringing with them nearly two decades of jangling guitars, wistful lyrics, and an iconic whistled hook that refuses to age. But they didn’t open with it – at least, not quite.

Instead, they opened by teasing the audience with a warped, distorted version of “Young Folks,” and it was a clever bit of misdirection, because while “Young Folks” may have been the gateway for many casual fans, Peter Bjorn and John had something else to show. Beneath the indie-pop polish lies a full-bodied, bass-forward rock sound, one amplified by their live performances.

The show was a full playthrough of Writer’s Block, the band’s career-defining third album, which holds up in a heartbreakingly nostalgic, but still ‘groove alone in your bedroom’ way. From the opening track of the set, a haunting call-and-response of “Poor Cow,” to the fuzzed-out dissonance of “Objects of My Affection” the band reminded the crowd why this album left such a mark on the 2000s indie landscape.

In addition to the Writer's Block tracks, the band also performed songs from other albums, including "Breakin' Point" from the album of the same name, "Living a Dream" and "Gut Feeling" from Darker Days, and "Second Chance" from Gimme Some.

Between songs, the band, made up of Peter Morén, Björn Yttling, and John Eriksson, kept things light. Their chemistry hasn’t faded, and neither has the charm that made Writer’s Block such an endearing oddball in the indie canon. During “Up Against the Wall” Morén hopped off the stage and made his way through the crowd, allowing longtime fans who'd been singing along for the past 20 years the opportunity to sing it with him.

One of the night’s most sentimental moments came in the form of “Teen Love,” a cover of fellow Swedish band The Concretes, that they promised to play every time they’re in New York. Longtime fans knew the reference (they released the cover as a single back in 2004) and everyone else just felt the warmth.

Perhaps the most surprising part of the night was just how muscular the set felt. For a band often pegged as delicate or “twee,” Peter Bjorn and John delivered a surprisingly guitar-and-bass-heavy sound that made a strong case for their rock credentials. The mix was loud and relentless in the best way.

And yes, when they finally did play the full version of “Young Folks,” it hit like a well-earned encore, even if it technically wasn’t one. The crowd whistled along like it was 2006 all over again.

Peter Bjorn and John proved they’re not just the band with the whistle, they’re the band with the riffs, the groove, and the staying power. Writer’s Block still aches in all the right ways, and live, it hits harder than you’d ever expect.

Connect with Peter Bjorn and John on Instagram, Spotify, and their website.