<Tr> <Td_colspan="2"> List of Gossip Girl episodes </Td> </Tr> <P> "Belles de Jour" is the 66th episode of the CW television series, Gossip Girl, as well as the season premiere of the show's fourth season . The episode was written by Joshua Safran and Stephanie Savage and directed by Mark Piznarski . It originally aired on Monday, September 13, 2010 on the CW . The episode filmed several scenes in Paris, a move that was heavily promoted by the show's network and commended by critics . A promotional video entitled "Oh Mon Dieu" used a French rendition of Nancy Sinatra's "These Boots Were Made For Walking" to advertise the season premiere . </P> <P> The episode received generally favorable reviews, with critics and fans praising Katie Cassidy for her performances as Juliet Sharp . The fourth season premiere opens with Serena van der Woodsen (Blake Lively) and Blair Waldorf (Leighton Meester) spending their vacation in Paris to move on from their troubles . Vanessa Abrams (Jessica Szohr) returns to New York and finds Dan Humphrey (Penn Badgley) living with Georgina Sparks (Michelle Trachtenburg) and a baby, while Nate Archibald (Chace Crawford) attempts to move on from his breakup with Serena, he befriends Juliet Sharp (Katie Cassidy), a girl with ulterior motives for helping him . </P> <Table> <Tr> <Td> </Td> <Td> This section needs expansion . You can help by adding to it . (December 2012) </Td> </Tr> </Table>

When do serena and blair go to paris
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