The phone rings -- seven or eight calls in less than 15 minutes. There's a reporter from the BBC on hold. Then a photo editor, on a tight deadline, from People magazine.

They want an interview.

They want a photograph.

They want a piece of Simmie Knox.

"This is surreal, all very surreal," says Knox, sitting -- right foot flat on the floor, the left one tapping -- inside his single-car garage turned studio, adjoining his four-bedroom Silver Spring home. "They Can't Take That Away From Me," on his favorite Hank Jones CD, plays in the background.

"I mean, I've been here all this time. I've just been 'under the radar,' so to speak, some sort of a secret -- that's what my friends say." He laughs.

The phone rings.

"Excuse me," he whispers to a visitor. "Hold on a sec."

Knox isn't a new discovery. The 68-year-old is well known among a certain coterie, having painted some of the most respected names in government (Supreme Court Justices Thurgood Marshall and Ruth Bader Ginsburg), entertainment (Bill Cosby) and sports (Muhammad Ali and Hank Aaron).

But his latest two portraits are another matter. And since their lavish unveiling Monday in the White House's East Wing -- after talk of the "self-taught artist," the "son of a sharecropper," the "first black American to paint an official presidential portrait" grabbed headlines -- everyone, in an instant, took notice. Is it that in the world of portraiture, a black man, especially a poor black man reared in the segregated South, is a rarity? Or is it that Knox's portraits of Bill and Hillary -- oil paintings on linen, two years in the making -- are, quite simply, that impressive?

Is it both?

"You know," says Knox, "at the end of the day, the work always speaks for itself."

The phone rings again.

"I've been getting so many calls," Knox says to the person on the line. It's Bill Cosby -- whose help, in the past 20 years, jump-started Knox's career, with commissions for 12 portraits of family and friends. "With art, a person must believe in himself or herself in order to find the very best. That's what Simmie is doing," Cosby says. Knox's portrait of Cosby's son Ennis, painted in 1997 after he was murdered, hangs over the fireplace in the entertainer's Manhattan home.

"Our family is very grateful for this gift," Cosby continues. "It is a portrait that projects every inch and every centimeter of our son."

Cosby goes on, "No one is more deserving of this success."

Knox was born in Aliceville, Ala., to Amelia and Simmie Sr., who divorced when he was 3. The young Simmie moved to Mobile when he was a toddler, to live with his paternal Aunt Rebecca and Grandpa Ben. He loved baseball. Hank Aaron was a neighbor, and sometimes they and other kids played. But after Knox was hit in the eye with a ball, a doctor urged him to take up drawing to retrain his eye muscles.

It wasn't until 1961, when he returned from a full day of school and work -- Delaware State College in Dover in the morning, a textile factory in Milford at night -- to sit in front of a mirror and paint his first self-portrait, in pastel, that he made two conclusions: He was angry at the world. He wanted to be an artist.

"You begin to realize, at that age" -- he was 26 -- "in those times, that you were suffering for silly reasons," Knox says of segregation. "Once in your life, at that one moment, you'll sit and you'll look at yourself. I mean really look at yourself, and ask: Who am I? What am I? What kind of person do I want to be? I knew, deep within me, that I wanted to be an artist."

So Knox made a leap, attending the Tyler School of Art at Temple University, where he also earned his master's, and, by 1971, participating in the 32nd Biennial of Contemporary American Painting at the Corcoran Gallery. It wasn't until 1972, when he moved to the Washington area, that he began to devote himself to portraiture. "Nothing," he says, "is more complicated."

He taught for a while, first at Bowie State College, then at the Duke Ellington School of the Arts. His contract at Ellington wasn't renewed. "They wanted to take a new direction," is all he has to say.

So he painted and painted, first the still lifes -- pots, with some cherries, strawberries and pears -- then the portraits. He and his wife, Roberta, and their kids, Zach and Amelia, would come to Eastern Market on the weekends, leasing a 5-by-7-foot space to sell Knox's stills.

One of his portraits, that of Frederick Douglass -- "a truly great American figure," Knox says -- is "buried somewhere in the Smithsonian downtown." It has been there since 1975, he says.

Those were the days, the difficult days when they lived in a cramped Adams Morgan two-bedroom, one bedroom for the family, the other Knox's studio.

"You just have to wait for the right moment," he says now, taking a sip of pink lemonade, wiping his brow with a napkin. The phone rings. Roberta, 57, picks it up. "The right moment came -- slowly."

Then came Cosby. Then came more clients. Then came the Clintons.

Knox had a feeling about Bill Clinton, he says.

"When he came to office, I said to myself, 'If I ever had a chance, this would be it.' It came to be."

So in 1992 Knox went to the White House, his portfolio in tow. "They probably didn't take me too seriously then," he says. "I was trying to get someone's attention, to let them know that I wanted to be considered."

The recommendation of Justice Ginsburg clinched the deal. That, and the fact that Knox had painted "most of my friends," Clinton told him.

So at this moment, there is recognition and, with it, success: Knox says he charges from $9,500 to $60,000 for each portrait.

"I never know what's around the bend now. It's surreal, I tell you. Surreal. But I'm delighted. I know it won't last. I know there's much work to do," Knox says. "Only difference is, I don't know who's going to be on the other end of the phone."

The phone rings, yet again -- a reporter from the News Journal in Wilmington, Del.

Artist Simmie Knox, at his studio in Silver Spring, painted the portraits of Bill and Hillary Clinton that now hang in the White House."I've just been 'under the radar,' so to speak, some sort of a secret -- that's what my friends say," artist Simmie Knox says of his recent acclaim.