The most recent guest on James Corden’s regular Carpool Karaoke segment (which is potentially getting its own TV show soon) was Gwen Stefani, who appeared on the late-night show back in March to sing one of her new songs. The two of them rolled through some of Stefani’s biggest hits, both solo and with No Doubt, and then were joined by A-listers George Clooney and Julia Roberts, and everyone sang “Hollaback Girl” and Queen’s “We Are The Champions.” Watch below.