When 16-year-old Lesley Hornby was discovered in 1966, her skinny frame, freckles, blond pixie cut and heavy false lashes made her an instant sensation. Renamed Twiggy, she stood apart from sultry, upper-class models like Jean Shrimpton — she was working-class, her father a carpenter, and at 5-foot-6, petite and childlike. "Girls from working-class families didn't become models," Twiggy, now nearly 77, said recently at Bottino restaurant in Manhattan. Yet she embodied London's youthquake and mod scene, her face launching cosmetics, clothes and lunch boxes.

A new documentary by director Sadie Frost, "Twiggy: The Woman Behind the Icon," arriving in America this month, traces her 60-year career beyond modeling. After four years working with photographers Barry Lategan, Cecil Beaton, Bert Stern, Richard Avedon and Helmut Newton, she pivoted to film. Ken Russell cast her as lead in 1971's "The Boy Friend" opposite Christopher Gable and Tommy Tune, earning two Golden Globes. She later starred on the London stage, recorded albums, designed fashion lines, and earned a Tony nomination for 1983's "My One and Only" with Tune.

Frost's film shows Twiggy navigating invasive crowds, leering talk show hosts, and a condescending teen interview with Woody Allen — who she stunned by turning his "favorite philosopher" question back on him. Her poise, she says tearfully, comes from her father Norman: "Dad became my rock when Mum would go into hospital," referencing Nell Hornby's mental illness struggles. Aging doesn't bother her: "I don't spend a lot of time thinking about what I look like."