Celebs Step Out For Stella McCartney at London Fashion Week

London Fashion Week is off to a good start; in addition to checking out the gorgeous runway collections, we're also spotting a bevy of celebrities making their mark on the stylish scene. Hollywood girls and fashion insiders, like Kate Moss, Rihanna, and Alexa Chung, all flocked to Stella McCartney's intimate Fall '12 dinner presentation — complete with a fashion flash mob — looking fresh and modern in their sleek and sexy attire. See who else attended the fashionable fête in the slideshow now, then check back later to see Stella McCartney's Fall '12 collection.