Zoe Trope

Zoe Kazan, the 28-year-old star and screenwriter of the slyly subversive new romantic comedy Ruby Sparks, skips the sunglasses. The July sun is blazing down on the Boston Public Garden as we walk toward the famous Swan Boats, but she doesn't even squint. During conversation she tends to lock in your gaze with her huge, expressive blue eyes--which, with her heart-shaped face, give her the slightly otherworldly, out-of-the-past aura of a silent-film star like Louise Brooks or Lillian Gish.

Another sign that she's a visitor from another time and place: she listens to her parents. She is one of two daughters of Oscar-nominated screenwriters Nicholas Kazan and Robin Swicord, who wanted Zoe to stay out of the movie business until after college; at Yale, she dutifully stuck to student productions. Since graduating in 2005, she has won mostly supporting parts in 16 films, from the prestige drama Revolutionary Road (as the young secretary who catches Leonardo DiCaprio's wandering eye) to the mainstream comedy It's Complicated (as Meryl Streep's giddy daughter) to the indie sleeper The Exploding Girl. Her breakout role, however, may prove to be one that she wrote herself.

In Ruby Sparks, Calvin (Paul Dano, Kazan's real-life boyfriend), a onetime wunderkind author with a serious case of writer's block, finally finds inspiration in a character named Ruby (Kazan). And somehow Calvin quite literally inspires Ruby--she springs to life, appearing in his kitchen one morning, blithely eating cereal. Calvin's idealized girlfriend is a classic movie stereotype that critic Nathan Rabin dubbed the Manic Pixie Dream Girl: quirky, ebullient, adoring and, since she's puppet to what Calvin puts on page, absurdly malleable. Except this manic pixie strikes a blow on behalf of all the real girls when she turns out to have a mind of her own.

The genesis of Kazan's spin on the Pygmalion story might be traced back to a bit of secondhand advice from actor-screenwriter-director Warren Beatty, who once told Dano that every actor should be making his or her own work--looking for material and maybe generating it too. "I firmly believe in that," Kazan says. "We are in the most insane waiting game of a business, and the only way I have stayed sane is by giving myself another creative outlet."

Dano, who's also 28--and best known as the callow preacher whose milkshake is drunk by Daniel Day-Lewis in There Will Be Blood--started reading the script while Kazan was still writing it. (Almost immediately, he asked if the parts were intended for them. The answer: not consciously, at least not at first.) "Ten pages in, I said, 'We should give this to Jon and Val,'" Dano says--meaning Jonathan Dayton and Valerie Faris, the husband-and-wife team who directed him in the Oscar-winning comedy Little Miss Sunshine. They asked Kazan to revise the script in 2010 just as she was opening on Broadway as Harper Pitt in Angels in America; she soon found herself writing feverishly backstage between scenes to meet her deadline. "I thought, This is the worst possible timing, but you have got to suck it up and do this, because this is an opportunity, and you've got to prove yourself to them," she says.