Gossip Girl, Blake Lively, Mary Katrantzou
Courtesy of The CW; Getty Images

With a new episode of Gossip Girl on Monday, we have a sneak peek at the hottest looks from the show! One outfit you’ll see: Serena van der Woodsen (Blake Lively) in a printed dress from London-based designer Mary Katrantzou’s spring 2011 collection. “It’s flattering,” Katrantzou told InStyle.com of seeing her designs on celebrities. “[The clothes have] always been on a woman with a strong presence.” For more looks from the new episode, titled “All the Pretty Sources,” click through the gallery. Catch Gossip Girl on Monday, November 21st at 8/7c.

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— Caitlin Petreycik, reporting by Lindzi Scharf