Green Day have surprised fans at San Diego Comic-Con by playing ‘Basket Case’ on top of an ice cream truck – check out footage below.

• READ MORE: Green Day – ‘Saviors’ review: their best work since ‘American Idiot’

The band appeared at Gallagher Square outside Petco Park on Friday (July 24) to promote their upcoming coming-of-age film Nimrods.

Billie Joe Armstrong climbed onto the roof of a Mister Freezie’s truck bearing the film’s title and performed the band’s 1994 hit, with Mike Dirnt and Tré Cool eventually joining him in the unique setting.

Armstrong went on to throw ice creams, T-shirts and cassette tapes into the crowd, while the trio later climbed inside the truck itself, handing out frozen treats to the assembled fans.

The Black Phone actor Mason Thames and The Office star Jenna Fischer, who both appear in Nimrods, were also present to watch the performance, alongside the film’s writer and director Lee Kirk.

Check out footage from the surprise appearance below.

Green Day frontman Billie Joe Armstrong surprised attendees at #SDCC with a surprise performance outside Petco Park!

His new film #NIMRODS is in theaters August 14. Get tickets on Fandango – https://t.co/cmsNq3Q5Vs pic.twitter.com/BMIwnnSWIh

— Fandango (@Fandango) July 24, 2026

I don’t care if Green Day playing Basket Case on an ice cream truck at San Diego Comic Con happened to you it should’ve happened to me instead pic.twitter.com/BVNjDljqGH

— lady stardust (@cinethanhunt) July 25, 2026

@livenation

If this whole music thing doesn’t work out, @Green Day would run an epic ice cream truck…@Nimrods, the new movie from the minds of Green Day, hits theaters August 14th.

♬ original sound – Live Nation Concerts

The Nimrods film will receive a limited release in UK cinemas on August 11, before arriving in US cinemas on August 14.

Developed by Kirk alongside Green Day, it follows three friends, played by Thames, Kylr Coffman and Ryan Foust, who travel from Kansas City to Los Angeles after mistakenly believing that their band has landed a support slot with Green Day on New Year’s Eve.

The cross-country road trip is inspired by Green Day’s own exploits and the years they spent living in a tour van before the release of their breakthrough 1994 album ‘Dookie’.

The film also stars Ignacio Diaz-Silverio, Keen Ruffalo, Fischer, Angela Kinsey, Mckenna Grace, Fred Armisen, Bobby Lee and Sean Gunn. It was originally developed under the title New Years Rev, before being renamed Nimrods earlier this year in reference to Green Day’s 1997 album ‘Nimrod’.

Green Day have also announced an accompanying soundtrack, which will be released on Friday (July 31) and features 22 career-spanning songs by the band, alongside music by The Paradox, Ultra Q, Mckenna Grace and Analog Dogs – the fictional group at the centre of the film.

The album includes the new Green Day song ‘I’m Never Gonna R.I.P.’, as well as four previously unreleased live recordings from a performance at the Palladium in Los Angeles featured in the movie.

Elsewhere, Armstrong has recently been playing shows with his covers band The Coverups. At two concerts this month, they were joined by Iron Maiden frontman Bruce Dickinson for renditions of David Bowie’s ‘All The Young Dudes’. They also performed Nirvana’s ‘Drain You’, which Armstrong dedicated to late L7 bassist Jennifer Finch.

Green Day released their latest studio album, ‘Saviors’, in January 2024. In a four-star review, NME called it their “best work since ‘American Idiot’”, praising the group for combining “the best of Green Day” with a renewed sense of purpose.