03/19/2011 12:15 pm ET Updated May 25, 2011

Paul Giamatti and Amy Ryan talk Win Win

Onscreen in Tom McCarthy's Win Win, they interact like a long-time married couple.

In fact, actors Paul Giamatti and Amy Ryan barely knew each other before they accepted the invitation of old friend McCarthy, who told both of them, "I've written something with you in mind."

"Paul and I had been ships passing in the night - a few years ago, he was leaving a production of The Three Sisters as I was joining it - so I was nervous at first," says Ryan, 41. "We're both shy people. But once we were on the set, that all melted away. And he was one of the most easy-going people to work with I've met."

Giamatti found that Ryan locked in to a certain quality of her character that he found impressive: "She captures this thing just unbelievably well," says Giamatti, 43. "Every time the camera would roll, her eyes would harden in a way that was amazing to watch. It was just the slightest change. But she became a completely different person."

In McCarthy's Win Win, which opened in limited released Friday (3/18/11), Giamatti and Ryan play Mike and Jackie Flaherty, a couple in New Jersey whose lives are turned upside down when they take in the grandson of one of Mike's clients. Mike, an elder-law attorney, has become the guardian for one of his clients - and the grandson shows up unexpectedly (and turns out to be the answer to Mike's prayers: a would-be star for the high-school wrestling team Mike coaches in his spare time).

Mike is as much a pragmatist as Jackie, who's fiercely protective of her young children - and, eventually, of Kyle, the visitor in her home. Yet, at heart, the couple is decidedly normal - two people in a loving marriage coping with the problems that life sends their way.

Which meant that, for both Ryan and Giamatti, the characters were kind of a stretch - in the sense that both actors have built careers playing people who are the opposite of happy.

"He's playing normal and I'm playing good," Ryan says with a smile.

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