“It was the first time I understood how you could get so wrapped up in a role that it could sort of take you down,” Natalie Portman explained in a recent interview with Entertainment Weekly. “There were some nights that I thought I literally was going to die.”

Portman revealed this and more details of what it was like to film Black Swan, a unique thriller set in the mysterious world of the professional ballet.

The actress trained for the role, in which she plays professional ballet dancer Nina, for one year. She lost a great deal of weight, fell in love and delivered a performance that’s making many critics take notice. She is currently nominated for a Golden Globe for her work in the film.

"Everyone was so worried about who was going to want to see this movie," she explained. "I remember them being like, 'How do you get guys to a ballet movie? How do you get girls to a thriller?' And the answer is a lesbian scene. Everyone wants to see that." That much talked-about scene takes place with co-star Mila Kunis, who plays a rival ballerina in the film.

Black Swan is currently in theaters nationwide.