To play the physically demanding role of "Neytiri" in the worldwide phenomenon Avatar, Zoe Saldana took up wushu martial arts, archery and horseback riding. But she tells Rachael there was another aspect of her preparation that she got into a little too much. "Because I was playing a creature that was conceived from thin air, I had to go through a program of dehumanizing myself," Zoe explains. "Things as simple as nodding or shaking your head to respond to something were things that the Na'vi didn't do - that's human behavior. I remember sitting at the table with my family and if they asked me if I wanted mashed potatoes, I would hiss at them! And they were like, 'OK, she's in Neytiri mode!'"

Zoe is now the face of Calvin Klein, and she and Elle creative director Joe Zee show you how your underwear can also be worn as outerwear!