"Sorry, can you hear me?"

Francesco Carrozzini yelled into his phone Friday night following the world premiere of Franca: Chaos and Creation, the filmmaker's portrait of his mother, Franca Sozzani, the longtime editor of Italian Vogue. by then, the red carpet swarm (Naomi Campbell, Valentino Garavani, Riccardo Tisci, Donatella Versace, Colin Firth) had passed and the screening had gone over well, leaving some in the crowd in tears. He had made it to the after party, a dinner hosted by Valentino, somewhat intact.

"I cannot hire a writer to write me a more perfect day," said an elated Carrozzini, whose first film had been four emotionally trying years in the making. He shouted over the party: "I wanted to get on the phone before I get completely fucked up!"

It was a cathartic moment for Carrozzini. When his father was dying five years ago, Carrozzini, then a photographer who was moving into directing music videos for A$AP Rocky, Beyoncé, and Lana Del Rey (whom he dated for a time), realized how little he knew about the former advertising executive who had split from his mother when he was four.

"He was never around," Carrozzini explained. "It was always my mother. I just wanted to turn my attention to what was left of my parents — my mother — to capture her." So he began taking a camera with him on their walks together. "It was very organic," he said of the process. "It was not like, 'We're going to make a movie.' It was more that I wanted to spend time with her. Slowly, slowly, slowly, it built into something real."

Initially, Sozzani assumed it would be a biopic. "That's what she wanted!" said Carrozzini. "To not be involved too much."

Sozzani is the longest-serving of any of the Vogue editors save Anna Wintour (they started at the same time), landing atop the Italian Vogue masthead in 1988. But her lengthy tenure has been in spite of her headstrong ways, not because she shied from rocking the boat. As is recounted in the film, Condé Nast International chairman Jonathan Newhouse considered firing her immediately after she took over because of the radical changes she was making. Over the years, Sozzani has explicitly confronted issues of plastic surgery, domestic violence, and racism in fashion inside and on the cover of her magazine.

While Sozzani's private concerns have become public crusades because of her position, she has always been reluctant to expose much of her private life, even to her son. "Work-wise, she was always who she was," said Carrozzini. "But we definitely got closer as mother and son over while making the film."

It came out during the process that Sozzani gave birth to Carrozzini while his father was still married to another woman, a subject that might never have been up for discussion otherwise. "Only the film allowed me to ask these questions," said Carrozzini. "This is not something I would've asked at the breakfast table. But there was a camera there, so I used it."

By no means is Carrozzini under the impression that this is a balanced, clear-eyed biography of his mother. "Her work I viewed as a journalist, but herself I viewed more as an exploration," he explained. "Not all of the truths have to always be expressed."

While Carrozzini is using the project as a launching pad into a filmmaking career (he will also be creative directing the House of Peroni exhibition, featuring famous friends like Catherine Martin and Vanessa Beecroft, opening September 8 in New York), he is mostly just relieved that his mother is happy with the final cut.

"She was pleased with the audience reaction," he said. Apparently, Valentino had emerged from the screening in tears.

"Yes, she was very happy," Carrozzini repeated, as if to reassure himself. Then he laughed.

"It would never have come out if she wasn't."

Watch: Giovanna Battaglia talks to Francesco Carrozzini before the premiere: