(Fortune Magazine) -- In 1982, Chris Gardner was just another go-getter in the training program at Dean Witter's San Francisco office, making $1,000 a month. He was also homeless. Gardner couldn't afford both day care for his 20-month-old son, whom he was raising alone, and a place to live.

So for a year he and Chris Jr. slept where they could - cheap hotel rooms in West Oakland, a shelter at a church in the Tenderloin, under his office desk, even, on occasion, the bathroom at the Bay Area Rapid Transit MacArthur station. He remembered the words of his mother, Bettye Jean Triplett, another single parent, who grew up during the Depression outside Rayville, La., where slavery was still a living memory: "You can only depend on yourself. The cavalry ain't coming."

Looking up: Gardner is enjoying watching his life turn into a major movie.

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So Gardner worked, making 200 calls a day to snag clients for Dean Witter. "Every time I picked up the phone," he recalls, "I knew I was getting closer to digging myself out of the hole." Within five years he had opened his own institutional brokerage firm in Chicago called Gardner Rich, which is still thriving today.

Then, in 2002, a story on local TV set in motion a series of events that will culminate this December, when a movie based on his life, "The Pursuit of Happyness", hits the theaters, with Will Smith playing the lead role.

And that is just the beginning. At 52, Gardner has a new goal: to become a household name. "Oprah did okay," Gardner says of the woman who is clearly one of his role models. "She's helping people, and she's making a ton of dough."

In May he released a memoir, which has the same title as the movie; it is now No. 7 on the Washington Post bestseller list. He has an agent at William Morris, a literary agent at Zachary Shuster Harmsworth, a publicist with Rubenstein PR, and a speaking contract with Keppler Speakers. He and Mark Clayman, an executive producer on the movie, have also formed a company called Chris Gardner Inc. to turn him into a brand.

Among their ideas: another book, a CD of songs that have inspired him, a daytime talk show, and a reality-TV show with the same folks who did MTV's Real World, in which Gardner will lead a team of people into blighted neighborhoods to help families in need.

On a hot late-July day in Chicago the humidity is stifling, and at the offices of Gardner Rich, a few blocks from the Sears Tower, the star of Chris Gardner Inc. is rustling through the papers on his desk. Gardner and his 14 employees work in a two-story building that looks like a squat glass box.

The office décor is as distinctive as the boss's life story. Gardner's desk is a 12-foot-long gleaming metal tail wing of a DC-10. Mounted on the wall are two life-sized plaster elephant heads. Gardner, 6-foot-3 with a graying goatee, dresses in a style both breezy and impeccable: loose-fitting white linen shirt, cornflower-blue Bermuda shorts, and leather slippers. Gardner's quirks (he wears two watches, one on each wrist, to make sure he's always on time), his people skills, and his powerful personal story do have a made-for-TV resonance to them.

Except that at this moment, as he smokes a Kool, he sighs and declares, "I'm tired of talking about myself." Right. Not only is he speaking to Fortune (and Entrepreneur, the San Francisco Chronicle, Tavis Smiley, and so on), but he has also booked 50 speaking appearances.

It is only Gardner's willingness to talk about himself that makes his plans plausible. Sure, he's something of an operator. His period of homelessness -devastating at the time - has become the dramatic center to his life story, the part that makes people stop and listen. But his sincerity is also compelling. Gardner is using his personal history - plus his persistence and manifest charisma - to sell the sense of possibility that he never lost.

Born in 1954 in Wisconsin, Gardner didn't know his father growing up, and his mother was married to an abusive man. At 18, Gardner graduated from high school and joined the Navy. He worked as a medic in North Carolina, then left the service in 1974 to work at a veterans' hospital in San Francisco. One day he saw a red Ferrari and, intrigued by the beauty of the car, asked the owner what he did for a living. Stockbroker, the man replied. From that moment, Gardner determined to become one too.

In 1982 he started at the Dean Witter training program. By this time he was sharing custody of an infant son. But his girlfriend decided motherhood was not for her, and Gardner began raising his son alone. The boarding house where Gardner lived did not allow children, and he struggled to find an alternative - thus the long nights at the shelter or the BART bathroom.

All the while Gardner held his job and slowly worked his way up and, by the end of 1983, into an apartment in what he calls "the ghettos of Oakland." He worked at Bear Stearns (Charts) as a broker for 3½ years before starting Gardner Rich. (There is no "Rich" at the firm, of which Gardner owns 75%. The rest is owned by a hedge fund. He picked the name because he considers Marc Rich, the commodities trader pardoned by President Clinton in 2001, "one of the most successful futures traders in the world." The two have never met.)

The brokerage firm, with assets of $475,326 in its last financial statement, earns its revenues from commissions on trades it does for its institutional clients. Mellody Hobson, president of Ariel Capital Management in Chicago, which has done business with Gardner Rich for ten years, says it is "one of the top-tier firms we use for trading."

Gardner eventually got his Ferrari but these days drives a jet-black Bentley. His son, Chris, is now 25 and trying to make his way into the music business. His daughter, Jacintha, 20, is a business student.

For all his élan - he favors bespoke suits and Maui vacations - Gardner was a low-profile success story until late 2002, when a San Francisco TV station aired a segment about his occasional volunteer work at Glide Memorial Church, where he used to stand in line for food.

Lynn Redmond, a television producer, saw the segment, looked up Gardner, and suggested he tell his story on ABC's newsmagazine, 20/20. "My first reaction was, 'Why me?' " Gardner says. "I was scared to death. My position was, if you want to do a piece about someone with some houses, some money, and toys, then no. But if you want to talk about someone who tried to do something with their life, with their family, and with their community, then I'm all for it."

The show ran on Jan. 17, 2003. Watching that night was Clayman, 39, a TV-actor-turned-producer, who is now working with Gardner on other projects. In a pivotal moment, the camera crew brought Gardner and his son to the bathroom they slept in back in 1982. Standing inside, Gardner declared, "A lot of hard decisions were made right here about, "What are you going to do with your life?' "

Fired by the idea of turning Gardner's story into a movie, Clayman showed the 20/20 clip to the producers at Escape Artists, who then sent it to Will Smith. "It made people come together and say, 'Let's go all out,' " says Todd Black of Escape Artists, which produced "The Pursuit of Happyness" (the curious spelling comes from a sign that Gardner saw when he was homeless).

Gardner flew out to Smith's home in L.A. for dinner so that the actor could study him, an experience Gardner describes as "surreal." He spent as much time as he could on the set during the 59 days of shooting, though some scenes were difficult to watch.

Driving through the streets of downtown Chicago in his Bentley, Gardner reflects on how the story of his life has taken on a life of its own. "Look, you know what I do know? All this could be real crazy," he says. "But I do believe, with all my heart, that some of the things that I had to go through were God's way of getting me ready for what He wants me to do."

In other words, Gardner wants his story to inspire. And because he is at heart a businessman - he still runs Gardner Rich, though he has delegated much of the day-to-day management - he also has ideas on how to make money while doing it. "This one TV producer I was talking to told me, 'The next Oprah is going to be a man,' " he explains. When asked if he was the next Oprah, Gardner says cheerfully, "You never know."

People are responding to his story. A table in Gardner's office is piled six inches high with letters - offers to speak, requests for political donations, and pleas for help from people who feel they can relate to Gardner's past. On occasion, Gardner will pick up the phone and call someone who has written in about a personal crisis.

"I find myself saying over and over: 'Baby steps count. But you've always got to be moving forward,' " says Gardner, who usually limits his assistance to phone calls because he says hope is sometimes all another person needs.

The Gardner gospel of persistence, progress, and faith is spreading--and the movie's not even in theaters yet. "His life is going to change a lot from what he knows," says Black. Gardner, too, can hear the rumbling of oncoming fame. It may not be the cavalry, but something's coming.

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