Kristen Stewart premieres `Camp X-Ray` at Sundance

Los Angeles: `Twilight` actress Kristen Stewart attended the special screening of her new movie `Camp X-Ray` at the ongoing Sundance Film Festival.

The 23-year-old `Snow White and the Huntsman` star was all smiles as she posed for the photographers at the Eccles Center Theatre, reported Ace Showbiz.

Stewart looked casual in skinny jeans and a striped shirt topped with a jacket. She rocked side cornrows and her trademark tousled hairdo. She was joined by co-stars John Carroll Lynch, Peyman Moaadi, Lane Garrison, Ser`Darius Blain, Tara Holt, Joseph Julian Soria, and writer/director Peter Sattler.

The film follows a young woman who joins the military and ends up as a new guard at Guantanamo Bay, where her mission is far from black and white.

To prepare for her role, Stewart said she met with military people and "watched a lot documentaries."