CHICAGO -- It was just a movie set, but in a moment it showed Chris Gardner where he'd been -- and how far he'd come.

There with actor Will Smith -- who was playing Gardner, a former homeless man turned millionaire -- Gardner stood in what looked like the train station bathroom where he once slept a quarter century ago.

Suddenly he was overcome with memories of teaching his 2-year-old son to never, ever open the locked bathroom door, no matter how hard someone pounded on the other side. It didn't matter that he now had three homes -- one a condo in New York's Trump Tower -- or that he'd gone from selling his own blood to buying Michael Jordan's car.

"I had to get out of there," he said.

The story of how the 52-year-old Gardner did just that, climbed out of homelessness and became a millionaire stockbroker with his own 15-employee Chicago firm, is being turned into a motion picture, due out in December. It's also the subject of Gardner's own just-released book, "The Pursuit of Happyness." The spelling of "happiness" is intentional.

Even in the realm of rags-to-riches tales, Gardner's story is unique. Take, for example, the events that led to his descent into homelessness.

A medical supplies salesman barely making enough money to support his girlfriend and baby, Gardner had one of those Hollywood moments in a San Francisco parking lot in 1981 when he spotted a man looking for a place to park his red Ferrari.

"I said to him, 'You can have my [parking] place, but I've got to ask you two questions. What do you do and how do you do it?"' recalled Gardner.

The man was a stockbroker. Gardner didn't know a single stockbroker or even what one did. But the man said he made $80,000 a month -- $50,000 more than Gardner made a year.

Gardner found a brokerage firm willing to hire him and quit his job. But when he showed up for work he learned the guy who'd hired him had been fired. Gardner's job was gone.

Then, days before a scheduled interview with Dean Witter, a loud fight with his girlfriend brought the police to his door. The next thing Gardner knew they were asking him for $1,200 to clear up some unpaid parking tickets.

They may as well have asked for $12 million. Gardner spent 10 days in jail.

When he was released, his girlfriend and son were gone. He had no money, no home and the only clothes he had for his job interview the next day were the ones he wore to jail.

How was he going to explain showing up wearing jeans and paint-splattered Adidas shoes?

"I couldn't think of nothing that could top the truth," he said. He went with that and got the job.

Today, signs of his success are everywhere, starting with an office that includes a gleaming desk made of a DC-10 tail wing, African art work, boxing gloves and photographs autographed by Muhammad Ali.

. Sharing space with pictures of his adult son and daughter are photographs of Gardner with Nelson Mandela, and a vase full of dirt that Gardner brought from Mandela's yard after visiting the former South Africa president.

He no longer has the Ferrari he bought from Jordan.

Gardner, who never went to college, has contributed tens of thousands of dollars to education, writing checks for as much as $25,000 to teachers, janitors, bus drivers and others who work at schools.

Gardner is focusing much of his attention now on South Africa, trying to persuade major investors to invest $1 billion there -- an effort praised by South African officials.

"In the current state of our economy, creating an investment fund is critical," said Yusuf Omar, South African Consul General in Chicago, who recently stopped by Gardner's office.

For Gardner, helping South Africans pull themselves up makes perfect sense.

"Everything I've learned working on Wall Street, 25 years, to be able to make a difference in the lives of a lot of people and we all make money, it (doesn't) get any better than that," he said.