In September, Pirelli announced that they were working with photographer Annie Leibovitz on their 2016 calendar. But this wasn't to be like any other Pirelli calendar. For the first time in its 50-year history, Leibovitz was ditching the supermodels and instead looking towards 13 of the world's most influential women, like Serena Williams, Rookie founder and editor Tavi Gevinson, Patti Smith and Yoko Ono – all aged from 19 to 82.

Unveiled in London today, Leibovitz attended the premiere with Gevinson and fellow calendar star, Chinese actress/activist Yeo Chen, where the black and white portraits were seen for the first time. "I still can’t believe the women who agreed to do it, did it," beamed Leibovitz.

In a film, premiered today, writer Fran Lebowitz quipped – "perhaps clothed women are going to have a moment". Jokes aside, the new direction for the Pirelli calendar – which has previously seen faces like Adriana Lima and Gigi Hadid grace its pages – signals a much-needed shift in global attitudes towards women, particularly when it comes to ‘beauty’ – which, Patti Smith, who was also shot for the series, reiterates is important to be seen as both on the inside and out.

Leibovitz, who shot her first Pirelli calendar in 2000, described the shoots as "straightforward and direct", revealing that they lasted no longer than an hour each and were witnessed only by a small amount of people, but with no "Pirelli people" present. She added: "I love to take something that you wouldn't expect and make something out of that and I'm not afraid of that.”

“I love to take something that you wouldn’t expect and make something out of that and I’m not afraid of that” – Annie Leibovitz

While all the women were invited to keep their clothes on, Williams and comedian Amy Schumer appear partially nude, in their underwear, with the comedian sipping on a cup of coffee. However, Schumer revealed that Leibovitz encouraged her to “slump over and let your stomach out”, before admitting that she had never felt more beautiful.

Set out like a book, each portrait comes accompanied with a paragraph on each woman's achievements too – from filmmaking to world class athletes, writers, rockstars and activists. Although refusing to call it a "watershed moment for women" when asked, Leibovitz said, "We did accomplish something together and I am very, very proud of it, and I'm proud of Pirelli for taking that step. It shouldn't be such a big step, but it is a big step."

The full Pirelli 2016 calendar features Yao Chen, Natalia Vodianova, Kathleen Kennedy, Agnes Gund (with her granddaughter Sadie Rain Hope-Gund), Serena Williams, Fran Lebowitz, Mellody Hobson, Ava DuVernay, Tavi Gevinson, Shirin Neshat, Yoko Ono, Patti Smith and Amy Schumer