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Rooney Mara

NEW YORK, NY - JANUARY 31: Actress Rooney Mara attends the premiere of "Side Effects" hosted by Open Road with The Cinema Society and Michael Kors at AMC Lincoln Square Theater on January 31, 2013 in New York City. (Photo by Ilya S. Savenok/WireImage)

What Were They Thinking?!

This week's worst-dressed crew includes Lindsay Lohan, Rose Byrne, and Christina Applegate. -- By Matt Whitfield