"IT'S ABOUT images. You're creating fantasies in the heads of the audience. And so you have to have them yourself, those images within you."

People say Virginia Johnson seems to actually turn into Blanche DuBois in Dance Theatre of Harlem's "A Streetcar Named Desire." Willowy and fragile, she wanders sinuously through the ballet, yearning for a world that never was. People ask how such depth and richness can be projected by a ballet character.

"Of course we all went to the movie when it was revived last fall," the lean, regally beautiful dancer said on a quick visit to her home town here before the troupe opens its Tuesday-through-Sunday engagement at the Kennedy Center. "I read the play, I took acting lessons, went to museums. You spend a lot of time getting into the character, thinking what kind of person she is. You have to fill your head with the person."

That's in her spare time. That's after the eight hours of daily practice, "every single day, the same exercises, the rote work, the routine--it can be wonderful to take a class, beautiful, but there are days when everything hurts, when you don't think you can stand to do one more stretch, do always more than the last time, always better. And this is just the exercise, to warm you up. The rehearsal comes after."

She had been dancing since the age of 3, but even when the pioneering black ballet star Arthur Mitchell lured her out of New York University to join his new ballet company--there were only four dancers then--she wasn't sure she wanted to make the commitment. She still didn't think she was going to be a dancer.

"It's not just the energy, it's the concentration it takes. You just don't have time for anything else. I was so apprehensive that I didn't quit college but took a leave of absence."

That was in 1968, a lifetime ago for Virginia Johnson, now drawing raves all over the world for her lyrical, majestic dancing. It takes character to deliberately postpone the rest of your life for the total immersion that is ballet. She lives alone, has little social contact, eats one (whopping) meal a day, no lunch, no snacks, plays the recorder now and then, is doggedly trying to finish college, one course per semester.

She smiled. "But it's such a short career."

She tried choreography. "I'd rather go to the dentist and have all my teeth pulled out than do that again." She doesn't think she could teach. Broadway and Hollywood mean nothing to her. She is a dancer.

This season she has been performing the sensational solo that Geoffrey Holder originally choreographed for his wife, to the haunting Songs of the Auvergne.

"It's a dream come true. It is exactly what dance is. You're not on point--Holder is always true to his West Indian self--but that makes it freer. I grew up with that music. The whole stage just vanishes and you're on top of a mountain with the wind in your hair and you're musing, daydreaming, and it's another world."

Her mother, an adult-education specialist in Washington, and her father, a retired Navy physicist, encouraged her from the start with dancing lessons ("Saturday mornings with Therrell Smith, the neighborhood teacher, it's what little girls do") and art and music. At 13, she won a scholarship with the Washington School of Ballet, performing in Washington and even in a mime piece with the National Symphony at Lincoln Center, moving on to study modern dance at NYU ("What a time, I lived in the Village and got a taste of New York and all those incredible things I'd never dreamed existed!"). She had been there only a year when on a whim she auditioned for Arthur Mitchell.

She doesn't give her age because she is suddenly feeling sensitive on the subject, but the fact is people say the great days are just beginning for Virginia Johnson.

"After it's over I want to do something entirely different, like trekking through Africa for the National Geographic," she mused. "I'm very good at not thinking about the future."