Billie Eilish made a surprise appearance on stage with Green Day on Thursday to kick off one of two star-studded concerts in Los Angeles put together to raise funds for people affected by deadly wildfires in California this month.

The concert will also be screened live at select AMC Theatres and and Regal Cinema locations in the U.S. If you will be on the move, iHeartRadio, the national audio partner for the event, will also feature the FireAid concert across over 860 radio stations in the U.S., digital platforms, and the iHeartRadio app.

FireAid, featuring Billie Eilish, Lady Gaga, Sting, Red Hot Chili Peppers and others in a fundraiser for Los Angeles-area wildfire relief efforts, is the latest event to combine music and philanthropy