George Clooney & Julia Roberts Sing 'Hollaback Girl' With Gwen Stefani for Carpool Karaoke!
This has be the most epic Carpool Karaoke segment yet!
George and Julia seemed to know every word! They also sang along to “We Are the Champions.”
Watch the latest Carpool Karaoke below featuring Gwen and some very special guests!
Gwen Stefani Carpool Karaoke With James Corden