“For a festival, we’ll come and say, ‘We’re gonna die out here tonight’,” Hyunjin explains backstage, hours before Stray Kids take to the stage in London’s Hyde Park. “Ooft!” the group’s leader, Bang Chan, exclaims from behind him, the expression on his face suggesting he’s not ready to go quite that far for the occasion. Come stage time, though, what seems like an extreme way of phrasing the eight-member boyband’s passion for performance doesn’t feel quite so exaggerated.

As Stray Kids race on stage at BST – becoming the first male K-pop act to headline a major festival in the UK – an enormous red banner emblazoned with their name unfurls magnificently. In the background, their live band play a beefed-up, instrumental version of ‘Lalalala’, all crunching rock riffs and ferocious drums. It feels like, instead of a festival performance, the group are heading into battle – a feeling that doesn’t dissipate when the banner drops to the ground. Once it’s out of the way, a graphic of a red flag, also emblazoned with the Stray Kids name, billows on the screen behind them. It’s clear they mean business, here to lay claim to hearts and minds.

As you’d expect, then, for the most part, this performance goes extremely hard. ‘S-Class’ is a speaker-shaking opener that feels like a demonstration of the power the boyband are about to display. ‘Thunderous’, which sees all members stride down the runway to deliver their complex choreo on the b-stage, is precisely as the title suggests – a storming early contender for set highlight. The thumping, prowling ‘Domino’ gets an electrifying refresh via a breakbeat dance break and, later, the triple threat of ‘Back Door’, ‘Maniac’, and ‘God’s Menu’ threaten to take things to brutal new levels, the latter peaking with blazes of fire shooting up from the stage.

Throughout, the group’s rappers set the pace, flawlessly delivering their fast-paced bars with ease. Whenever Changbin or Han in particular are on the mic it feels like you’re watching a masterclass in flow – it’s just a shame that the sound can’t always stay as crisp to give the audience the full effect of their talents. But even when Stray Kids leave the stage for an outfit change, the energy doesn’t drop, thanks to their backing band stepping into the spotlight to deliver a riff-heavy interlude that includes part of Led Zeppelin’s ‘Kashmir’.

For all the booming tracks that make up the core of this set, though, there are also lighter moments. ‘My Pace’ sounds brighter than ever, its “na na na na” refrain uniting the park in a big singalong, while ‘Charmer’’s Afrobeat rhythms and ‘Lonely St.’’s expansive, emotional scope counterbalance things – a necessary moment of relief so the boyband can return to battle mode once more.

It’s been five years since Stray Kids last performed in the UK with a show at O2 Academy Brixton, which feels tiny compared to tonight. “Back then, there was some uncertainty – we didn’t know whether we had fans in the UK,” Lee Know admits backstage. Although they’re much more comfortable in that knowledge these days, their London fans make sure to make their presence felt tonight. They bellow back every word, even before the group first appear on stage, and come close to matching Stray Kids’ intense energy.

If the crowd is having a good time, then the same can be said of Stray Kids. They look like they’re having the utmost fun, whether they’re jumping around in a circle during ‘Social Path’ or darting from one side of the stage to the other during ‘Back Door’. As the set reaches what should officially be its end – after a euphoric, fireworks-punctuated ‘Miroh’ and a reprise of ‘Topline’ – there’s one member in particular who doesn’t want to go home. “You guys want one more song?” Bang Chan asks before Feli starts yelling into his mic in his deep, rumbling rasp: “One more song!”

A fierce ‘Megaverse’ follows, but it’s still not the end. “One more?!” Felix begins shouting as Stray Kids’ leader tries to wrap things up. “Mate, mate, mate,” Bang Chan addresses him, arm around his shoulders. “You’ve gotta hype everyone up, and then we’ll do one more song.” Challenge accepted. Felix roars at the crowd before turning his attention to his bandmates: “Stray Kids, do you want one more? Let’s get it!” ‘Haven’ is a fitting way to both end the night and measure up to the rapper’s boundless enthusiasm, its chorus taking Hyde Park higher one last time as Stray Kids finally make their exit, London well and truly conquered.

Stray Kids played: 

‘S-Class’
‘Freeze’
‘Super Bowl’
‘Topline’
‘Thunderous’
‘Item’
‘Domino’
‘Lonely St.’
‘Social Path’
‘Charmer’
‘My Pace’
‘Back Door’
‘Maniac’
‘God’s Menu’
‘Lalalala’
‘Victory Song’
‘Miroh’
‘Topline’
‘Megaverse’
‘Haven’