Several years ago, Malcolm Gray was watching an Elvis Presley tribute show on Pay Per View when a still photograph appeared: the iconic 1956 shot of the 21-year-old rock ‘n’ roll star playfully romancing a blonde fan backstage. Gray’s eyes widened. “My God, come here!” the electrical engineer shouted to his girlfriend, Barbara, now his wife. “They’ve got you on that big screen. Does Priscilla know who you are?”

“No,” Barbara said, nonchalantly, from the other room. She had seen that photo hundreds of times over the past half-century. “I was before Priscilla, Malcolm.”

“The Kiss”—as the photograph is sometimes called—is in fact the most enduring of the 3,800 exposures that photographer Al Wertheimer made of Elvis Presley, many of the best taken during a two-day period in June 1956. While chronicling the rock prince on the threshold of becoming the King, Wertheimer, then 26, famously caught Elvis on the road and at his home in Memphis with his family and entourage. But that prize frame has become one of the classics in the rock-photography canon: Elvis, in a stairwell at the Mosque Theatre in Richmond, Virginia, minutes before a concert, darting a mischievous tongue toward the deliciously reciprocating mouth of a mysterious girl in black.

Many have compared the picture to another moment snapped 11 years before: Alfred Eisenstaedt’s 1945 “V-J Day in Times Square,” shot for Life, of a sailor and a nurse spontaneously embracing the day World War II ended. But while both images have remained photographic whodunits for decades, nearly 20 people have come forward now and again, purporting to be the subjects in the Times Square shot. In contrast, no one has ever emerged with a legitimate claim as Elvis’s blonde. And with good reason. In the photo, her features are largely obscured. And to make matters more difficult, Elvis, throughout his career, was known to have had scores of dates and trysts with fans and companions.

“I never bothered to ask her name,” says Wertheimer, an energetic 81-year-old German émigré, sitting in his New York brownstone brimming with Elvis books, photos, and memorabilia. “And she never bothered to tell me.” As a result, for 55 years Wertheimer has called her simply Elvis’s “date for the day.” What’s more, ever since the picture was published, no one on the Richmond music scene, or in Elvis’s inner circle, seemed to know who she was.

But how could they not? This was a Kim Novak look-alike, dressed for Saturday night—sexy, flirty, wearing four-inch, plastic Springolator pumps, rhinestone fan earrings, a black chiffon spaghetti-strap dress, and a see-through purse festooned with faux pearls. Whoever she was, this was not a girl to forget. As evidenced in the 48 shots that Wertheimer took of her that day—many of which show her facing directly into the lens—she had fetching dimples, brows sharply penciled in black, and a teasing smile that tugged at the corners of her mouth.

By her own admission, real-estate manager Barbara Gray, though a natural blonde, doesn’t much resemble that babe from ’56. “But, hey, what do you want? I was 20 years old,” she says good-naturedly, sitting in the kitchen of her Charleston, South Carolina, home, and speaking in an accent that smacks of street-smart Philly. “Now I’m 75. I was very thin and very stacked. Every time I would go to get fitted for a bra, the sales ladies would say, ‘Gosh, you have such lovely breasts.’ And I would think, ‘Well, I don’t know. Are you hitting on me?’”

When the photo first appeared—in a September 1956 magazine entitled The Amazing Elvis Presley (a 100,000-copy, 35-cent-an-issue newsstand “one-shot”)—Barbara, known as Bobbi, got a kick out of it. In those days she was a sometime dancer, a shoe-store clerk, and an unabashed party girl. And she certainly got around. The singer Pat Boone, she says, with whom she’d become rather friendly when he played Charleston the year before, called her to give her some grief. “Boy,” he supposedly needled her, “you’re in pictures all over the place with my biggest rival!”