Sometimes, the difference between a best and worst style star, is merely one key accessory. Fashionista Rachel Bilson chicly added tan, roll over boots to her simple ensemble, achieving a look that is sure to be copied! Ana Ortiz, on the other hand, ill-fatedly added grey leggings, instead of black, to her patterned frock, which resulted in a not so hot look.

How did Sir Ian McKellen achieve best dressed status? Check out the gallery to find out!