Gwen Stefani already packs more than enough star power for an epic Carpool Karaoke episode, but James Corden managed to rope in silver screen legends George Clooney and Julia Roberts, making for some truly memorable hijinks during the episode. Stefani kicked things off by singing her biggest hit, No Doubt’s “Don’t Speak,” which was pretty high energy for a brutal breakup song.

Stefani then tried to teach Corden her rapid-fire rap on her solo hit “The Sweet Escape,” and the funnyman rose to the challenge and nailed it in a light-hearted segment. The pair then had a crack at “Used to Love You” and “Rich Girl” before picking up Clooney and Roberts. Check out the episode below.

Of course, the awesome foursome then had to lay into Stefani’s anthem, “Hollaback Girl,” with a whole lot of bleeped-out swear words to boot. Corden then invited Clooney and Roberts to speculate on the meaning of “hollaback girl,” to which Clooney said, “Ain’t no hollaback, meaning if there’s guys on a construction site yelling at a girl, she’s not going to turn back—she’s not that kind of girl.”

Corden then asked Stefani about the meaning, and she allowed, “I think that’s pretty close. It’s your interpretation of the song. I don’t want to project what I thought. The real inspiration behind that song, I would never say. All I’ll say is that I won.” With perfect comedic timing, Clooney then dropped the iconic line from “Hollaback Girl,” deadpanning, “This s*** is bananas—B A N A N A S.” You can hear the original song below and see if you think Clooney’s theory was on the money.

One of the most interesting sections of the episode followed, where Corden asked Clooney and Roberts to name their favourite lines from their onscreen roles. Clooney said he liked several lines from O Brother, Where Art Thou? and said “I’m a Dapper Dan man” stood out. Roberts’ choice was her line to Clooney’s character in Ocean’s Eleven “You’re a thief and a liar,” to which he replied, “I only lied about being a thief.”