It’s common to see a movie where someone goes mad, but in this role you’re actually going in the reverse direction and going sane. What was that like?
It was an interesting thing trying to figure out, not having seen where she comes from, exactly what level of madness it was going to be at the beginning. And it really came from David. He just said, “Go for it, give it as much as possible — I can always bring you back.”

My understanding was that you guys did a lot of research and based the performance on real medical studies. Is that right?
Yeah, I did about four months reading before we started, not necessarily because I had to, but just because I wanted to for this one, because it’s such a fascinating subject. But also because I didn’t understand where the character was coming from. A lot of times you play people who are similar to you in some way — not in every way, but there’ll be something you can grab onto and go, “OK.” But with this one there was actually nothing. When you’re playing someone with a mental illness, I think it’s wrong to think that there isn’t a logic to the behavior. I really wanted to understand the logic behind the behavior in order to play it. It took a couple of months to get my head around it.

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