The Voice judge Gwen Stefani got in James Corden's Range Rover for "Carpool Karaoke" on Wednesday's Late Late Show, and it starts out as a relatively sedate round. The highlight of the early going is when she breaks down the fast part of the lyrics to "The Sweet Escape" for Corden (and you kinda wish she didn't, you know?). But just when you start to think, "This is kind of boring, I'm going to turn this off," two very special guests show up and crank this up into a "Carpool Karaoke" for the ages: George Clooney and Julia Roberts. Two of the most famous people in the world sing Gwen Stefani's "Hollaback Girl." This sh--, as they say, is bananas.

Gwen Stefani and James Corden, <em>The Late Late Show</em>Gwen Stefani and James Corden, The Late Late Show

(And when Gwen Stefani says she'll never say who inspired "Hollaback Girl," she's being a little disingenuous; everyone knows it's about Courtney Love, which frankly makes Stefani's assertion that she "won" pretty mean.)

(Full disclosure: TVGuide.com is owned by CBS.)