Lady Gaga surprised the crowd at The Dirty Pearls' show at New York City's Gramercy Theatre on Saturday night. Gaga, who had just finished singing jazz standards at her own show with Tony Bennett, ditched the gowns for panties, torn fishnets and red boots when took the stage to rock out to the band's hits, as well as a cover of Billy Idol's "Rebel Yell."

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The Dirty Pearls are an NYC-based rock band who have been longtime friends with Lady Gaga — they opened for Mother Monster's Born This Way Ball tour and she even shouted them out in her 2011 track "Heavy Metal Lover" — "Dirty Pearls and a patch for all the Rivington Rebels. Let's raise hell in the streets, drink beer, and get into trouble."