'Everyone thinks models are stupid' – the iconic Twiggy on the '60s, fame and why age shouldn't define you

"I had been approached many times over the last 20 years or so about doing my life story, and for whatever reason it didn't work out or it wasn't something that I felt comfortable with. It's quite a big thing to put into somebody's hands."

The circumstances which eventually led to the new film were rather fortuitous. Actress and fashion designer Sadie Frost had been a guest on Twiggy's podcast Tea with Twiggy to promote her first documentary – about the iconic '60s fashion designer Mary Quant – and during the episode Twiggy asked her if she had plans for any more features.

Frost's response was that she had especially enjoyed doing extensive research into the fashion and cultural scene of the '60s, and would like to find somebody else to cover from that period. And then it struck her: Twiggy herself would be the perfect subject. So, the following week the pair met up for lunch and it quickly became clear that it was going to be a fruitful collaboration.

"I loved the idea, number one, that she's a woman, and could understand a lot of what I went through," Twiggy explains. "Because there's quite a lot of parallels in our lives – she started at a very young age, she was a model, she's an actress, she's been very much in the public eye and dealt with what you have to deal with when you're in the public eye.

"So I thought she'd understand a lot... that we could talk about things that she would understand without me having to explain it."

For her part, Frost found the process of exploring Twiggy's life and career a rewarding one, although she notes that when someone has been in the public eye for such a long time, you really have to dig deep to get new insights.

"I had to keep pushing and pushing but also respecting Twiggy and not wanting to make her feel uncomfortable," Frost says.

"I wanted it to celebrate women, but I also wanted to look at how hard it could be for some women, especially in that time, if you came from the wrong place. How you had to be driven, how did you pave a way for yourself?"

Naturally the documentary spends a significant portion of its runtime focusing on the era when Twiggy first achieved fame. There's plenty of excellent archival footage – including some that the star claims never to have seen before – along with insightful contributions from a number of talking heads, including Dame Joanna Lumley and Dustin Hoffman, to provide both vital context and amusing anecdotes.

This chance to reflect on the exciting cultural period she helped shape was a rare one for Twiggy, who admits that looking back is not a pastime in which she often indulges.

"I never think about the past ever," she says. "We were at a screening yesterday at the V&A, and somebody asked about that. I said, 'I never get up in the morning and think about the '60s. It never crosses my mind!'

"I think about what I'm doing now, what I've got in front of me the coming week. I'm quite busy, which I love. I'm also very, very family-oriented... and I think that's probably what's helped to keep me grounded through this very mad business."

Still, did going back into the archives for the documentary give her a new perspective on any of those early experiences?

"When I first saw it, I was amazed how young I was," she responds. "You forget, because when you're 16 and 17, you kind of feel quite grown up.

"And then I look back, and I mean, I did look so young. And I was so young. That was the big thing that hit me. And I was thankful that I came through unscathed, really. But I had very good people around me."

The film also explores some of the clichés that are often lobbed at models, especially in the days when she first started. One – initially excruciating – scene sees her patronisingly questioned by Woody Allen, who asks her to name her favourite philosopher in what seems like nothing more than a mean-spirited attempt to catch her out.

But rather than folding under the pressure, Twiggy nonchalantly turns the tables and fires the question back at Allen, who immediately becomes flustered. How often did she have to put up with that sort of behaviour?

“There's always been that thing that models are thick and stupid," she says. "But as I said once – I think it's in the film, actually – I said to Graham Norton, I know a lot of thick and stupid people in lots of walks of life. I mean, how can you generalise?

"And most of the models – certainly from my era – went on to do wonderful things, Anjelica Huston, Susan Sarandon... I mean, there's endless ones. But you know, it's weird, that period... you can see by the way some of the photographers spoke to some of the models.

"And actually, I found Joanna Lumley's interview really interesting because she was that little bit before me, and she was like a working model, whereas what happened to me, I was thrown into the deep end right at the beginning, so I didn't have to do all that flipping around looking for work. My journey into becoming a big model was very different than most models!"

The film is more than just a snapshot of that moment in the '60s, though. Frost spends time documenting various aspects of Twiggy's life all the way up to the present day, covering her meeting with iconic British filmmaker Ken Russell and subsequent acclaimed acting career, her marriage to first husband Michael Witney and the tragedy which ended it, and her return to modelling with campaigns for Marks & Spencer and more recently Charlotte Tilbury.

"I love the fact that she covered my whole career in such depth," she says. "Because I only actually modelled for four years. It was meeting Ken Russell that really changed my life, because he cast me in The Boy Friend. And that was when I realised that's what I wanted to do – to go into performing.

"So the modelling career was actually quite short, really. I mean, I came back into it in the '90s, when Steven Meisel rang and said, 'Can I do a 10-page spread on you for Italian Vogue?' I mean, who am I to say no! And I was not a young girl at that point, so I was very flattered."

That evolution over the years – and her refusal to be defined purely by her early days as a young model – is a key theme of the film. Towards the end, it is remarked upon that often, when it comes to big stars, there's a cliché that they always stay the same age as they were when they became famous. Twiggy has always defied this.

"I hope it proves to all women – or men as well – but all women out there that age shouldn't define you," she says.

When we speak, Twiggy has already seen the film through a couple of times, but is looking forward to the London premiere, when she'll have the opportunity to watch it with multiple family members.

"We'll probably all have a few tears," she says. "I said to my older sister, Shirley, 'Bring a pocket full of Kleenex' – she'll probably cry all the way through! When I got my damehood, I got my sisters tickets to come along with my husband and my daughter and my stepson – and Shirley cried all the way through because she was like my second mum!

"But what's lovely is the reaction we did at the Q&A at the V&A. The audience were lovely, and actually a few women said, 'Oh, I cried all the way through. It reminded me of when I was young and so sweet.'"

But it's not just those who were there at the time that the film will appeal to.

"A lot of the people who write to me now are young people, they're like, 18 or 20 or 22," she says. "Because they love that period, for fashion, for music. And it's interesting. I mean, I got one last week from a young girl in China. And you know, I didn't know I was even known in China! But there you go – I am!"

Twiggy is now showing in UK cinemas.

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