What's She Done: The sexy star stole the show as the bumbling beauty in 'Mean Girls' (2004). She went on to haunt Kristen Bell on The CW's "Veronica Mars." Her role on "Big Love led to nabbing roles in 'Mamma Mia!,' 'Dear John,' and 'Letters to Juliet.'
What's Next: The blond will haunt audiences in the medieval thriller 'Red Riding Hood.' She is also slated to star in the futuristic thriller 'Now' with Olivia Wilde and Cillian Murphy.