Sombr brought out 5 Seconds of Summer at Lollapalooza, joining forces with the band for a rendition of ‘She Looks So Perfect’.

• READ MORE: Sombr at the BRITs 2026: “I love America, but I think music from the UK beats them”

The US pop artist played the Chicago festival on Thursday (July 30), telling the crowd a “special surprise” was in store before introducing the band. “Ladies and gentlemen,” he said, “the greatest band in the fucking world, 5 Seconds of Summer.”

Bandmates Luke Hemmings, Michael Clifford, Calum Hood and Ashton Irwin came out to provide backup on Sombr’s ‘Back to Friends’, before the vocalist put his own vocal spin on 5SOS’ breakout hit, ‘She Looks So Perfect’ – which you can watch below.

Sombr has been releasing a slew of new music recently, including last month’s ‘My Body Isn’t Ready’, as well as previous singles ‘Homewrecker’ and ‘Potential’, with all three making it onto Thursday’s set list.

Following his stint on the Lollapalooza stage, he’ll be heading out on a North American headline tour, and is also perform at Reading & Leeds later this month. His other summer festival appearances include Sziget, Rock En Seine and Electric Picnic.

SOMBRSOS! “Senhoras e senhores, por favor, recebam a melhor banda da porra do mundo: 5 Seconds of Summer” 🖤 pic.twitter.com/eJhflJXnqL

— Sombr Brasil (@SombrBR1) August 1, 2026

His debut studio album, ‘I Barely Know Her’, was released last summer. In a four-star review, NME called the record “smart, emotional and surprisingly upbeat”.

The singer spoke to NME at the BRITs 2026, where he was nominated for International Artist and International Song (‘Undressed’). Sombr said he felt “honoured” to be at the awards, and was “thankful for the British people for accepting” his debut album “with open arms”.

“I just love it here,” he told us. “It’s the music that comes from the UK [that clicks with me]. In my opinion, I love America, but I think acts from the UK just beat them, in terms of iconic acts.”

He cited the likes of The Beatles, The Rolling Stones, David Bowie and Elton John, as well as some legendary Manchester bands like Oasis and The Stone Roses.

Elsewhere, back in April, Sombr delivered a surprise duet with Billy Corgan at Coachella, where he also performed with Billy Idol, and covered a Radiohead classic.