How did you prepare for this darker, angrier role?

One of the things I liked thinking about was that you are not punished for your anger; you're punished by your anger. Somebody said that to me, or I read it. That there's not some moment when you're going to be called to task because you've been angry, but your anger itself is what punishes you, limits your life, and constricts you. I think that's true for Maggie. Her life is constricted, it's telescoped, it's gotta be about getting revenge on this guy when obviously it has nothing to do with this guy--it has to do with what's going on inside her.

What happens when love becomes an addiction?

It's almost never healthy when love becomes an addiction, is it? As we all kind of know, right? It's a funny movie because it's just about how far people will go when they're in pain. People behaving badly.

If Harry had abandoned Sally at the end of that movie, might she have flipped out and turned into Maggie?

Maybe. [Laughs.] Maybe, because she was very tightly wound, so she's exactly the kind of person who could have spun out in this kind of direction. 'Cause I think Maggie at heart is a sort of tightly wound, fragile person. I think she's kind of a blueblood in a way, with these delusions of being an artist that never happened. And then she gets dumped by this guy, and she kind of cracks, but she was likely to crack. But I do think this is just an episode in her life.

You studied journalism at N.Y.U., correct?

It was sort of like soft [journalism], I was more interested in Madison Avenue. I thought I'd be a really good neurotic person on a magazine staff.

You'd be writing for Vanity Fair? Maybe Vogue?

Yeah, in the food category. Food, or fashion, or personalities, that's what I thought I'd do.

So you have empathy for what I'm doing here.

Yeah--I understand what you're doing. I "get you."