In a tête-à-tête with Carine Roitfeld, it’s clear right away that the enigmatic former French Vogue editor-in-chief has a heightened sense of awareness — fitting for one of the most astute and influential figures in fashion. While I’ve interviewed her before, I am still amazed. She scans the room, picks up on visual cues and uncannily knows where the conversation is going, partly because she takes it there. She’ll speak at length and doesn’t slow down, not for a second, and all of it in non-native English.

The topic of this interview is the new documentary about her. Fascinating and revelatory, Mademoiselle C was conceived and directed by Fabien Constant, who spent four months trailing Roitfeld. It takes place in early 2012, the year she relocated from Paris to New York, post-French Vogue, to produce and launch her self-titled biannual, CR Fashion Book.

“I immediately said yes to Fabien because I am very spontaneous,” she says, in characteristic rapid-fire speech while cradling a cup of hot tea, her only demand wherever she goes. “It was a documentary about the new magazine, something for people to talk about. You need buzz. And now, when I see it, I think it’s very personal! But I told Fabien, ‘This is your film, you can do what you want. I open the door for you.’ He did everything. He chose the poster, he chose the name, the music, everything. He calls it Portrait of a Lady, not that I’m a lady.” The thought sends her into demure giggles.

The film chronicles the making of the debut issue and delves deep into her fabulous life. We see her coddling Kate Upton on a location shoots; hotly debating budgets and contracts back at the office (Condé Nast reportedly refused to let its contracted photographers work for CR Fashion Book); organizing a star-studded charity catwalk in Cannes; cavorting with the likes of Karl Lagerfeld and Donatella Versace; and hanging out with Beyoncé at the Met Ball. “We talked about babies,” she recalls of that night. “She showed me pictures of her baby, Blue Ivy, and I showed her pics of my granddaughter. There I was, sitting next to the biggest star in the world and we talked about babies.”

Asked to pick out a favorite moment from the film, she doesn’t hesitate. “The part in the film where Karl [Lagerfeld] is pushing the stroller [with her granddaughter]. Karl is very nice with children. I think that’s going to be an iconic moment.”

There is another memorable scene, in which she’s practicing ballet in her home with a trainer. She’s attempting the splits, which she finally achieves as the camera captures her agony. It provides a tidy analogy for her work ethic. “I was working on the theme of ballet for my second issue,” she explains. “It was my new obsession. I learned everything there is to know about ballet. Maybe people think I was being ridiculous in the film, but I don’t care. Ballerines work, work, work, and they have maybe half an hour on the stage. I think this is a bit the way I work, too. I like to push hard for a single moment.”

For her latest issue of CR Fashion Book — the third, hitting newsstands now — she has found a new new obsession: “Caravaggio, the Renaissance painter! I’m obsessed with the way he reinvented painting. He did things like street-casting and showing dirty feet. It was very real and raw. And I was thinking there is a lot of Caravaggio all around us everyday. The world is full of people who try to do things differently and find a new way of beauty. Otherwise things would look boring and there would be too much political correctness.”