Weezer and Foo Fighters have just finished an Australian tour together, and to celebrate the moment, they joined forces on stage in Melbourne to perform a cock-rock standard, Kiss’s “Detroit Rock City.” When I say “join forces,” I mean Rivers Cuomo came up to sing and shred a bit with the Foo Fighters, standing awkwardly in the middle of the stage as Grohl hopped, skipped, and jumped across it. “Are you ready, Rivers?” Grohl said in a joke Paul Stanley-esque voice at the beginning of the song. Rivers, deadpan and weaselly: “I’m ready to rock.” It sounds like what it is.