“I wanted very much to make a love story about parents and children,” director Mira Nair said in a Dallas interview about her new picture, “The Namesake,” based on the well-regarded novel by Jhumpa Lahiri about a traditional Bengali couple, wed in an arranged ceremony, that emigrate to the United States, and their son with the unlikely name of Gogol, who’s torn between his Indian culture and Americanization. “And I love the rhythm of laughter and sorrow in a film.

“What I wanted to do was to make the adaptation rest on two pillars,” the filmmaker–who made her debut with the Oscar-nominated “Salaam Bombay!” in 1988 and went on to direct such pictures as “Mississippi Masala” and “Monsoon Wedding”—explained. “One, the love story which I find rarely seen, the idea of strangers who marry and then learn to fall in love with each other, especially more so in a distant climate. And I loved to evoke the stillness of that generation, where you don’t need roses and diamonds and big proclamations of love—it’s really about sharing a cup of tea in a kitchen and the way you look at each other and the history in those eyes. I wanted very much to have that sort of quietude and unspoken love.

“The second [pillar] was the coming-of-age [story], the counterpoint of Gogol’s finding out who he is and finding out that he needs to go very far from his parents to understand, eventually, what they mean for him and who they were for him.” And, she added, to comprehend the depth of their love. “The ultimate folly of youth,” she said with a smile, “is that you think as a young man that you’ve discovered love for the first time, and you have no idea of the passion that your parents—who don’t touch—might have felt or do feel for each other.”

Much of the success of Nair’s effort, she admitted, depended on her cast, and in that respect she felt blessed. “An angel of casting flew over me in this movie,” she said, “because with every one [of the leads] it landed in the right place.”

The mother and father in “The Namesake” are played by Bollywood stars Tabu and Irrfan Khan, and Nair enthused about them both.

“Tabu is an amazing, brave actress who has a map of life in her eyes,” she said. “And that’s what I was looking for. I can direct a lot, but I can’t direct your eyes, what you’ve seen. And she had to play with conviction a dewy bride and the gravitas of a widow. And she’s seen this world. Also, this is such a saga about aging, and I didn’t want the latex horror show, the sort of superficial aging that’s plastered on you. It had to be from within. So it had to be with a great actress who internalizes that journey.” And Khan, she added, is actually “very different from Ashoke, the character he plays. He’s more like a singer, a John Travolta in ‘Saturday Night Fever’ kind of guy. And he just internalized that self-effacing, almost invisible person whom you miss when he’s gone.”

As for Gogol, Nair eventually cast American comic star Kal Penn, although by a circuitous route. “I didn’t know Kal existed, actually,” she said. “He was brought to my attention by my fifteen-year old son, who worships at his altar. And when he and his best friend, who’s sixteen, showed me Kal early on, when I’d just decided to do this film, I thought he was a comic goof, and that was that, and not the dashing guy I was looking for.

“But Kal wrote a letter to me during this whole domestic pressure at home—you know, every time I would put my son to sleep, he would say, ‘Mama, tell me in the morning it’s Kal Penn’—and then Kal wrote to me saying he was an actor because of seeing ‘Mississippi Masala’ when he was eight and realizing that people on the screen could look like him, and could he fly himself in and audition. And I said fine. And he came, and he was the real thing. He obviously had been Gogol in his life. He obviously understood that exact arc that Gogol had. And he had a great hunger for it. And when I met him, I felt his physicality was such that he could actually play the adolescent as well as the dashing young man. It was quite a wonderful thing to finally know that he was Gogol—and he certainly was. He’s a revelation—people are clearly celebrating him.”

That celebration is part of the warm reception “The Namesake” has received in its pre-release festival screenings. “I have never had a film that connected more,” Nair said. “It’s like an interactive experience. I think it’s a universal thing—millions of us have left a home for another, whether it’s India for America of Dallas for New York City. And it’s really about parents and children, and parenting, and the selflessness of a parent. It’s really been a rapturous kind of response.”