StyleWatch SpecialInside Burberry's Star-Studded Bash!
Posh, Gwyneth, Mary-Kate and more party the night away with the chic British label to celebrate its new headquarters and the last night of London Fashion Week
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MARY-KATE OLSEN
After playing bartender to kick-off New York Fashion Week, the design star helps close London Fashion Week in a long black coat over a tulle party dress and suede booties.
