Dennis Quaid, an actor who often plays a heroic or athletic figure, packed on the pounds to come to Pittsburgh in fall 2006.

He gained the weight to portray Lawrence Wetherhold, a Carnegie Mellon University professor trapped in a fugue of grief over the death of his wife. "Unlike me, the Jewish shlub that I am, I think he can't gain weight," at least not easily, director Noam Murro said in a phone call this week.

"He can eat 500 doughnuts and still be fine. We talked about it; it helped him in his posture, the way he negotiated the world. It was a very good thing."

Murro, a native-born Israeli who lives in Los Angeles, shot "Smart People" in Pittsburgh in just 29 days. With many of its scenes filmed inside campus buildings or a Friendship residence, the movie generally kept a low profile, arriving in town on the heels of "The Mysteries of Pittsburgh" and the Sienna Miller brouhaha.

He scouted in New York, Connecticut, New Jersey and elsewhere in Pennsylvania before settling on Pittsburgh to shoot the script by novelist Mark Poirier.

"You feel because it is a smaller place, there is a sense of family. You just believe it. ... It's a believable backdrop for that kind of story."

Family is central to "Smart People," which also stars Ellen Page and Ashton Holmes as Quaid's children, Thomas Haden Church as his adopted brother and Sarah Jessica Parker as a possible romantic interest.

Page, who plays a high school senior, made this movie before "Juno" turned her into an Academy Award nominee and cultural sensation. "I remember Dennis at some point said, 'She's the new Brando.' She's that talented," Murro said.

Murro, whose commercial work has been honored by the Directors Guild of America and other prestigious panels, looked at more than one school before gravitating to CMU.

"I thought that the way it looked and the way it felt seemed authentic to who Lawrence is. ... It's not the typical sort of neo-Gothic or Gothic or neoclassicist [design]. You don't see people smoking pipes, it doesn't feel like that," he said.

"It's a serious place where people are there studying, and that was actually important for the film."

Murro didn't feel the need to go into detail about Lawrence's late wife. Her clothes are still at the house, she is shown in a couple of photos, and Lawrence stumbles across an old congratulatory card from her.

"I think that her presence is there, and that's kind of the difference between melodrama and a dramedy," which is how Murro describes the movie. "You want her absence to be part of the narrative or the mood of the film rather than to show her."

"Smart People," he says, is about a family going through an awakening period, and change comes slowly as you age. "The older you get, the less you move. I mean, there are shifts, there are moves, but I think it's pretty ingrained."

Murro, a husband and father of children ages 7 and 4, says he doesn't want to sound like he's "the great teacher" when asked about the movie's lesson. "I want people to come out of it, think about their lives, think of the people who surround them, and I think family is the only relevant thing that there is."