62. Natalie Dormer
Biggest accomplishment this year: Becoming a series regular on HBO's Game of Thrones
Natalie Dormer has been the breakout star of this season of Game of Thrones, making the most of her screen time as the clever, scheming Margaery Tyrell. She has emerged as a scene stealer in a show bursting with excellent personalities, and her role will hopefully expand in future seasons. It also was announced recently that Dormer would also appear in three episodes of the CBS show Elementary, a surprise hit that will air its second season later this year. She's also got four movies slated to release in 2013, including a supporting role in The Counselor, a star-studded film also featuring Michael Fassbender, Brad Pitt, Cameron Diaz, Penélope Cruz, and Javier Bardem.