Today, Chris Gardner, the man Smith plays and on whom the movie is based, is a successful stockbroker. But for a year in the 1980s he found himself faced with a curious set of circumstances: single father to a young boy, a barely paid intern-trainee at a brokerage firm, and - suddenly - homeless.
Gardner spent night after night trudging the streets of the crime-ridden Tenderloin district of San Francisco, with all his earthly possessions on his back, diapers shoved under one arm, pushing the stroller with his toddler toward a homeless shelter. When the shelter was full, they slept in the park. Or under Gardner's desk. Or sometimes in the public bathroom of a subway station.
For Smith, playing someone on the losing end of fortune's whim was not nearly as formidable as portraying someone who was actually there on the set nearly every day of the shoot. To play the role, he had to be willing to strip away his movie stardom and put on someone else's skin, a process that Smith describes as a "terrifying" one. "It's very scary to adapt someone's life, and do it in two hours, and the person is there," he says. "In the first period, you say: 'I can't do this. No way.' Then the story starts to eat at you, and you say, 'Oh, I have to.' Then you meet the person, and it becomes clear how daunting the task is. It's someone's life. On top of my being a perfectionist - and trying to shoot for the idea of perfection in an imperfect science - it's a gut-wrenching task."
To help get there, Smith lost 25 pounds, grew his hair and donned glasses. But the harder work was on the inside. He had to drop a lot of his habits and tricks. His obsessive preparation. His tendency to make methodical lists: do the first take, angry; do the second take, frustrated. Peering through his lens, the director, Gabriele Muccino, made Smith give up the gloss and go deeper.
" 'You're posing,' " Muccino would complain, Smith says. " 'You can't trick me.' He'd say, `You're making faces as if you're hurt. I need you to take some time. And come back. And be hurt.' "
Smith reflects, "Acting is generally humbling. But it's much more humbling when someone can see you like that."
The actor also remembers the time Gardner took him to see the bathroom at the Oakland commuter train station, a place where Gardner and his son had slept on many nights. Smith asked to be left alone in the bathroom for a few minutes. He came out five minutes later. "He was not the same guy," Gardner recalls. "It was like a ghost jumped into his body."
The scene was shot later, on a set. In the film, Smith - exhausted, hungry, dirty, rejected from every shelter he has tried, and with his son in tow - pretends that they have landed in a prehistoric wonderland, and must crawl into a cave (the bathroom) to hide from dinosaurs. His son willingly beds down on cardboard and a coat. Slumped against the tile wall, his son's head in his lap, Smith locks the door and - as someone outside starts banging to be allowed in - a tear slowly crawls down his cheek.
"That's acting nirvana," Smith says. "You're not acting. You're slipping into the moment. I was there."
Opening soon across the Philippines, "The Pursuit of Happyness" is distributed by Columbia Pictures, local office of Sony Pictures Releasing International.