Caught in the Act!
05/06/2010 AT 06:00 AM EDT
After performing at the Met's Costume Institute Gala in N.Y., Lady Gaga kept the party going at New York's Royalton Hotel, where the pop diva danced the night away. Joined by pals like Justin Tranter from Semi Precious Weapons (the band is opening for the singer's Monster Ball tour), Gaga spent time in the deejay booth with Lady Starlight and also held court at a table full of fashionistas.
Meanwhile in Las Vegas, Joel Madden deejayed from his table at Moon Nightclub. The Good Charlotte singer was joined by friends at the club's weekly Bang! party, where he sipped vodka and Red Bull as he spun tunes. Earlier, Madden dined on lemon chicken and creamed corn at N9NE Steakhouse inside the Palms Casino Resort.
Paris Hilton, taking shots and acting "very single" at the weekly Bolthouse Tuesday Nights party at West Hollywood's Trousdale Lounge, an onlooker says. The heiress, who was joined by sister Nicky and Brandon Davis, showed off her dance moves and gave various male clubgoers kisses on the cheek before leaving to find another party.
By JENNIFER GARCIA, MARK GRAY and LESLEY MESSER
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