The two megastars gave a live debut to their version of Charli’s song “Guess”, from her feature-heavy remix album, “Brat and It’s Completely Different but Also Still Brat”. The arena was covered in bright “Brat-green” lights and lasers as the duo danced, sung and hyped up the screaming crowd.

@charlixcx love u billieeeeee and hbd!!! &lt3 @BILLIE EILISH ♬ original sound – Charli XCX

Their collaboration on “Guess” has earned them a nomination for Best Pop Duo/Group Performance at the 2025 Grammys. Both artists have claimed seven nominations each for the upcoming awards ceremony.

Charli has had an undeniable presence in pop music this past year – her album Brat and its deluxe and remix editions successfully stood out this year, with their infectious fusions of dance, hyperpop and rave music earning universal acclaim from critics. According to Metacritic, Brat is the highest-rated album of 2024 and the 14^th-highest-rated of all time. It managed to eventually secure the number one spot in the UK after falling second to one of Taylor Swift’s many variants of The Tortured Poet’s Department.

The album and phenomenon of “Brat summer” reached further than just music – politicians started co-opting the lo-fi aesthetic of her artwork’s green background and Arial font, most notably Kamala Harris during her presidential campaign. “Brat” was even named Collin’s Dictionary’s word of the year following its influence in pop culture.

Her minimalist but atmospheric live shows have been hailed by concertgoers and reviewers, celebrated as possibly the “best show of the year”. She’s shunned elaborate set pieces and backing dancers, performing solo in a mist of smoke and strobe lights, capturing the essence of the warehouse raves where she first started performing.

The “360” singer mostly takes on the crowd alone in what the Guardian calls “a glorious, one-woman triumph”, while occasionally joined by some of the stars featured on her remix album such as Yung Lean, Robyn and Caroline Polachek.

Billie has also had a fruitful year, releasing her third studio album Hit Me Hard And Soft to high praise and currently on a world tour that will hold its final shows in the UK next summer. Fans were left upset the other day after a video surfaced of a fan throwing an object at the alt-pop hero during her performance of the Barbie ballad “What Was I Made For?” – the audience gasped in shock as Billie gave a disappointed look, before carrying on her song like a true professional.

Charli has scheduled a 2025 arena tour with dates in both the UK and US and will also be headlining the Parklife festival in Manchester and the LIDO festival in Victoria Park. All her upcoming dates can be viewed on her website here.