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ET has confirmed that "Project Runway" judge and fashion designer Michael Kors is joining the teen ranks of The CW's guilty pleasure, "Gossip Girl," for one hot night this fall. Michael appears as himself during a New York Fashion Week episode the show recently taped.

The witty designer tells Women's Wear Daily that he's a diehard 'GG' fan: "I love the clothes, everyone is good-looking, the plot line is a riot. I love the show. They called and said, 'You are very 'Gossip Girl.' I thought, 'Finally, I am a teenager.'"

Joining him on the episode are heiress Tinsley Mortimer and Cristina Cuomo, editorial director for Gotham and Hamptons mags. "Gossip Girl" returns Sept. 1 on The CW.