How to Bewitch a Wizard

The sixth Harry Potter movie doesn't skimp on franchise staples: there's Quidditch-ing and wand-waving and potion-stirring, as well as the expected dastardly-deed-doing of Voldemort's crew. But for the first time, there's also (finally!) some serious romance. Hogwarts has become a hormonal minefield, navigated to mixed results: Hermione pines, Harry ogles, and Ron full-on snogs, spending a good chunk of the movie glued to blond classmate Lavender Brown. Brown's shrill, teen-queen glory is brought to life by Jessie Cave, a 22-year-old Londoner and newcomer to the franchise. Ahead of the movie's release, Cave spoke with NEWSWEEK's Sarah Ball about smooching, avoiding swine flu, and the utter agony of unrequited love. Excerpts:

Lavender, to put it lightly, is very aggressive in pursuing Ron. Why?
I think that she's misunderstood, really. She's insecure, I think, and her main problem is that she's just obsessed with Ron. She loves him. She's almost borderline under a spell: she is just entranced by him, and that kind of causes her to become a bit wayward. She's not really aware of how she's coming across to everybody, as a bit mad. She realizes pretty quickly that he has feelings for somebody else—Hermione—and she kind of reacts to that by becoming incredibly clingy and possessive and loud and annoying. But I think she's just got a big heart and she just wants to be loved, you know? (Story continued below...)

You play being heartbroken very well. It was so evident in your face.
She just feels so embarrassed, and very exposed at that moment, very raw. At that age, you become soooo heartbroken by boys, you develop such big crushes, and then you're soooo devastated when they don't work out. I really do feel her pain.

Do you remember this chapter of your own life?
Yes. It's always going to be incredibly hurtful when your love is unrequited. And there's an age where you remember things so vividly. I think that's why J. K. Rowling writes so brilliantly. She must have had these experiences, because otherwise she wouldn't have been able to write them so pitch-perfectly. It's great, because she really does transport everybody back to that period in their life. This book especially is so, so accurate of teenage obsession and hormones raging.

You are totally festooned with bows, bangles, headbands, every Topshop accessory imaginable.
She's a very girly-girl—she's like the type of girl that you could imagine you could hear coming a mile off because of her bangles kind of rubbing together. She's perfectly curled and coifed and ready to be seen at any occasion—very, very aware of how she looks. And very pink.

Are you like that in real life?
No, I'm definitely not as prepared as she is, and I'm definitely not as neatly intact at all times. It was a major decision to make her hair curly, and to make her very pristine. The headbands are something I wear in my life, too. But I'm definitely nothing like her; I wear glasses in real life and have a bit of a beak.