Acting has traditionally proved hostile terrain for models, and few cover girls have made successful crossings. But Cara, according to her colleagues in both fashion and film, appears to possess gifts that her thwarted predecessors lacked. For starters, she has become the preeminent model of her era through the brazen display of personality, that thing most models are now richly paid to hide. Far from a rare orchid that wilts in the breath of more noxious air, Cara, simmering with life on the runway, boils over with life off it. She has been called the next Kate Moss, but the similarities begin and end at their shortish stature (for their profession, that is: both are five-eight), English background, and penchant for late nights. Whereas Kate has retained an essential unknowability, Cara seems always to be declaring, “This is the real me!”

I feel this desire to throw away the story I’ve been telling for years. Cheers—to a new story!

The designer Erdem Moralioglu calls this her “characterful-ness,” a sort of elfin energy that animates her beauty. “In 20 years,” he says, “we may look back at this era and think of Cara the same way we look back at the sixties and think of Jean Shrimpton.” Karl Lagerfeld, the designer with whom she has become most closely identified, acknowledged her leavening effect on his industry when he called her “the Charlie Chaplin of the fashion world.” (It was that most precious of Lagerfeld confections: a compliment.)

Though DC wants her fit as a fiddle, Cara decides that a glass of red wine can’t hurt. Perhaps it will ease the passage of all that veritas she seems intent on spilling. “I feel this desire to throw away the story I’ve been telling for years,” she says, raising her glass. “Cheers—to a new story!”

The tale begins in the Belgravia neighborhood of London, in whose rows of white stucco houses aristocratic families live in the comforting proximity of families they have known for generations. Cara’s father, Charles Delevingne, is a property developer, and though he did not grow up rich, his looks and charm got him invited everywhere. Her mother, Pandora, a London society beauty in her day, is the daughter of the late Sir Jocelyn Stevens, a publishing magnate, and Jane Sheffield, lady-in-waiting to Princess Margaret and a charter member of the princess’s Mustique set in the 1960s.

“I grew up in the upper class, for sure,” says Cara, whose older sister Poppy, 29, is also a model, while Chloe, 30, a scientist by training, has moved to the country to raise her children. “My family was kind of about that whole parties–and–horse racing thing. I can understand it’s fun for some. I never enjoyed it.” But it was Pandora’s relapsing heroin addiction that may have been the defining fact of Cara’s childhood. “It shapes the childhood of every kid whose parent has an addiction,” she believes. “You grow up too quickly because you’re parenting your parents. My mother’s an amazingly strong person with a huge heart, and I adore her. But it’s not something you get better from, I don’t think. I know there are people who have stopped and are fine now, but not in my circumstance. She’s still struggling.” (Pandora is currently working on a memoir—about her battle with addiction and the eighties London scene that formed its backdrop—which Cara says she has mixed feelings about.)