Only 12 blocks from Broadway, where it first opened in 1935, "Porgy and Bess" will finally reach the stage of the Metropolitan Opera House next week. It's taken the show 50 years to move those dozen blocks, and some old-fashioned Met patrons are still arguing over whether it should be done.

For Washington baritone Charles Williams, it has taken about 20 years of training and experience to prepare for a lead in that historic production.

"It's still a dream," says Williams, a small, intense man in his forties who moves his hands expressively as he talks, sometimes slips into fluent German and occasionally breaks into song to illustrate a point. He has been waiting two years, since a successful audition in 1982, for the Met to give its first "Porgy and Bess."

He has left behind a successful career as a pop and operatic singer in Europe, living with his wife and two children in Alexandria and earning a nonluxurious living as a musician in the Washington area. He is the chairman of the voice department at the Selma Levine School ("I became the chairman when we hired a second voice teacher") and sings occasionally in recital.

On Feb. 6, on the stage of the Metropolitan Opera, he will become Sportin' Life, the charismatic but satanic villain who peddles "happy dust," sings "It Ain't Necessarily So" and tries to lure Bess away from Porgy.

Williams had sung the role four times in Europe -- "once in German, once in German and English, and twice in English" -- when he heard that James Levine was going to conduct "Porgy and Bess" at the Met.

"I was teaching . . . in Salzburg at a musical theater workshop," he recalls. "I said I'd like to get a chance . . . just an audition." When the chance came, with the help of a friend at the Deutsche Oper in Berlin, he says, "I jumped on the train from Salzburg and rode through the night to Bayreuth and I auditioned."

It could have been a terrifying experience, but Williams found that James Levine was "a dear, wonderful, friendly, open, down-to-earth Ohio boy."

"I sang for him -- that was in the summer of '82 -- and he said, 'Thank God.' And I thought, 'What does he mean?' He said, 'Thank God. I was so worried about this role.' I thought, 'Now is this some New York stuff he's giving me?' Because he's conducted all the greatest singers in the world . . . but apparently he was impressed."

Levine was evidently looking for a new kind of Sportin' Life, and Williams was the kind he wanted. The two discussed the concept of the role. "Sportin' Life is a real snake," says Williams, "but he wants something. The times that I've done it, I've done it as a straight, operatic villain, not a little guy with a derby and checkered suit doing song-and-dance man; I sing it."

There was a second audition -- this time on the stage of the Metropolitan in New York, where Williams will be singing the role. The timing was fortunate; after 20 years of singing in Europe, Williams had already decided to return to the United States and relocate in Alexandria.

According to Williams, this second audition went even better than the first. "He Levine said, 'Fantastic, Charles. Can you, just for fun, sing the second aria?' And I thought, 'Just for fun!' " The second aria is the one most firmly in the tenor range, and Williams is not a tenor; he is a baritone with good high notes. "So I did that . . . and I thought, well, he's brought me over here and they've heard me and I know I did a good job, but I'm sure there are seven that have sung, and they've already really cast it. But maybe they'll give me a performance or two or something because I did a good job.

"They called me the next day and said, 'Mr. Williams, we'd like to offer you the role of Sportin' Life.' And I said, 'That's very fine.' "

He still remembers the shuttle flight back to Washington: "I sat there looking at all the other people and I was thinking, I'm going to sing at the Metropolitan Opera, and I could tell all you people, but I won't. Because I don't have to. Someday, you will know."

Charles Williams was born in Haynesville, La., grew up in Detroit and Dayton, Ohio, and went to Los Angeles City College with a major in theater and a minor in music. He knew early what he wanted to be.

"At age 12 or 13," he says, "I can remember listening to the Met over the radio and loving it; I cried listening to 'La Bohe me.' " He describes his mother as a "black Lucille Ball" who taught him to dance.

His college studies were interrupted by service in the Army, which sent him to Germany. But while he was at college, he was interviewed for the school newspaper by a Filipino student. This young reporter eventually went to Germany with Williams, and the two were married in 1961 in Augsburg, West Germany.

As the discussion touches on his family, Williams pulls out his wallet, absently vocalizing, and proudly produces photos of his wife June (now a writer and editor), daughter Lynne (a freshman at Shenandoah College and Conservatory of Music with show business aspirations) and son Scott (in high school).

"After the Army I was going to go to Berlin to study for a year because I said, 'Well, I'm in Europe . . . Music! Singing!' . . . I had studied theater . . . And that one year turned into 20."

While his wife worked at the U.S. Press Center in Berlin, Williams pursued his musical career. "I could make a living in Europe singing, but not here," he says. "I did a lot of recitals, a lot of church music, oratorios, a lot of cantata work, radio recordings . . . mostly American music . . . spirituals, a lot of musical theater stuff. I've done all kinds of musicals . . . very little opera. And then I started doing a lot of television, variety-type stuff, and I was with a partner for several years. We had a two-man show where we did everything from soup to nuts."

He did not spend 20 years in Europe because of race, he insists, but because opportunities simply kept opening for him there. Now, he believes, it is becoming harder for Americans in Europe because a new generation of European singers has arrived to fill the ranks depleted after World War II, and "naturally, they want to take care of their own first."

"In Germany," he says, "people would try to get me to talk about the mistreatment of black people in the United States, to boost their own self-esteem. 'Hier, ist es besser' ('Here, it is better'), they would say, and I would answer, 'Nein, hier ist es anders' ('No, here it is different')."

Williams enjoys dropping a few names of celebrities he's met and worked with while abroad.

For example, he appeared in "Hair," "Godspell" and "The Me Nobody Knows" with Donna Summer "way back when."

Another old friend from Europe is Julia Migenes-Johnson, recently of "Bizet's Carmen" fame. The two toured together in Europe and were flown to Paris last March to do a television show. Williams chuckles, describing her as "a funny, wonderful person. Out of her mind, out of her bloody mind. Puerto Rican Greek, a mixture . . . and New York, too! In other words, a real American."

Around 1967 Williams met Gian Carlo Menotti while the opera composer was in Berlin to buy lights for the prestigious Spoleto festival in Italy. They talked about Williams' career as a singer, and Menotti asked Williams for his phone number and a tape. "One day, at 2 o'clock in the morning, I get a call in Berlin. 'Charles, the role in Spoleto is free. Are you interested?' And I said, 'Yes, yes!' And I realized when I got to Spoleto that he hadn't even heard the tape." In rehearsal, says Williams, Menotti is "Dr. Menotti and Mr. Hyde," flying into a rage with one singer, then turning around to act as charming as can be with the next.

The opera was "Il Furioso," and he was the only American in the cast. His international opera debut was well received.

Another thrill of Williams' life was meeting film great Ingrid Bergman at Menotti's birthday party that year. "She was standing over there, ponytail, no makeup, flat shoes, dress -- just nyuh -- you know, she looked like a peasant lady -- looking at me, and I was looking at her. And she came over and said, 'Mr. Williams, uh, I enjoyed your performance very much. Of all the people on stage, I understood your Italian the best.' " Quite a compliment, since Williams was one of only two non-Italians in the entire cast.

He will be more at home at the Met, and he is looking forward to it: "To sing in your own country at the house," he says. "Where do you go from there?"