When word got out that Kate Winslet was going to be in the upcoming Avatar, the world basically freaked out. Now, director James Cameron has revealed a little bit more details.

“She’s very excited about it. She blazed through for a couple of days of rehearsals and saw the world that we had created, and how we do the work, and she’s very excited,”James told Vanity Fair in an interview. He added that her character is part of the Sea people, “the reef people.”

“The one thing she did do is demand that she do all her own water work,” he said of Kate. “I said, ‘All right, that’s fine, we’ll have to teach you how to free dive.’ The other actors are up to three- and four-minute breath holds. We’ve already been doing underwater capture. We did a scene last week with six teenagers, well, actually five teenagers and one 7-year-old underwater holding their breath for a couple minutes and acting, actually doing a dialogue scene under water because they speak kind of a sign language.”