8. Elizabeth Olsen

2011 key role: 'Martha Marcy May Marlene.'

Before 2011, Elizabeth Olsen was known as the other Olsen sister; now, she's known as one of the year's biggest It-Girls, with a possible Oscar nomination in her future. For Olsen, it all started with the Sundance hit 'Martha Marcy May Marlene,' which stars the 22-year-old actress as an escapee from a cult. Olsen also appeared in two other festival faves: 'Silent House' and 'Peace Love and Misunderstanding,' opposite Jane Fonda.

Upcoming projects: In addition to her possible Best Actress nomination, Olsen has a host of other major projects lined up for 2012: 'Red Lights' with Robert De Niro, 'Liberal Arts' with 'How I Met Your Mother' star Josh Radnor and 'Very Good Girls' with Dakota Fanning. Not bad for someone whose first credit was as 'Girl in Car' in 'How the West was Fun,' a 1994 video starring Elizabeth's sisters, Mary-Kate and Ashley.