Katy Perry shows her vulnerable side


American pop sweetheart Katy Perry is revealing a vulnerable side as she attends the European premiere of her new film.{}{}"Part Of Me" premieres in London on Tuesday. It's a 3-D behind-the-scenes look at the ups and downs of the 27-year-old singer's life over the past year. {}Having spent most of it doing a world tour, fans are treated to performances, backstage antics and the occasional breakdown.{}{}Perry also lets the cameras follow her through the breakup of her marriage to British comedian Russell Brand. {}Directed by Dan Cutforth and Jane Lipsitz, "Part Of Me" hits U.K. theaters on Thursday.