Kate Winslet picks me up from the train station in her grey Land Rover Discovery and we drive to a house nearby which she is borrowing from a friend for a few weeks. We push through the front door and are immediately ambushed by her two dogs.

“Out the way, you little f---ers,” she says to them affectionately, and to me, “Do you like scrambled eggs?” She opens the fridge and apologises profusely for its barren interior. “I never normally have an empty fridge, I cook all the time – I’m always bloody cooking, I love cooking. There’s usually a colossal amount of food in our house.”

Winslet, her husband Ned and their 10-year-old son Bear usually live in a village half an hour away (her actor daughter, Mia, 23, is filming, and son Joe, 20, is travelling). But right now they are here on a short break between projects before Lee is released.

It’s a film she has been developing – on and off – for nine years, about the American photographer and model Lee Miller, who is known for being the muse of surrealist artist Man Ray, but whose major achievement was her photography of the end of World War II.

Her dispatches from the front line appeared in Vogue at the time, but the full extent was only discovered when her son came across her archive in the attic, after his mother’s death in 1977. He found a manuscript, 60,000 images and 20,000 vintage prints.

Miller was one of just four female photographers accredited as official US correspondents during the war. She was at the siege of Saint-Malo, the liberation of Buchenwald and Dachau, and was famously photographed in Hitler’s bathtub at his apartment in Munich. She was outspoken and fearless, and always the last to leave the party.

Winslet stars in the film and produced it, alongside fellow producer Kate Solomon and a stellar cast, including Josh O’Connor, Andrea Riseborough and Alexander Skarsgård. It was directed by Ellen Kuras and co-written by journalist Marion Hume. “I wanted to tell the story of the most significant years,” says Winslet, “and to redefine how a generation of people will come to view her – and hopefully change the perception of her as the ex-model who used to be Man Ray’s muse.”

Winslet radiates enthusiasm and passion, with a slightly insurgent edge. She is part netball captain, part pirate, and she charges deftly around the large kitchen island, chopping tomatoes, grinding pepper, whisking eggs, clattering forks, saying her piece.

Lee Miller was a badass, and Winslet feels a strong connection with her. “In many ways I felt more similar to her than almost any character I’ve played before. There’s so much of how she lived her life that I profoundly connected with, but was also inspired by.

“Even how she celebrated her physical self,” says Winslet, who is not afraid to take her clothes off in the film, and has recently spoken about how she ignored a crew member’s suggestion that she might want to sit up straight in order to disguise rolls of flesh.

“Stupid things you might consider as a woman – well, playing Lee made me think, I don’t give a f--- about any of that. I mean, I literally don’t give a shit. I don’t care. I would take all my clothes off in front of you right now. I just don’t believe in hiding the truth, actually.”

The film is based on a biography by Antony Penrose, who is Lee Miller’s only child from her marriage to the English surrealist artist Roland Penrose. There had been several attempts to turn the book into a film, notably by Nicole Kidman and, later, director John Maybury, both of which stretched over several years. Then Australian company Hopscotch bought the rights, under the auspices of producer Troy Lum, who was approached by Winslet at the Toronto Film Festival – and nobody is going to turn Kate Winslet down.

It was a struggle to start with. “It’s hard making films unless it’s a great big Marvel movie. There’s a lot of [she adopts the voice of a whiny, male, American director], ‘Well, why should I like her?’ There’s a certain generation of men who aren’t interested in women who had a troubled life and alcohol issues and were rude and brash. Lee said what she wanted and got what she wanted.

“The #MeToo movement happened, and suddenly there was this shift – women’s voices were being given a platform like never before. And the more time went by, the more we were thinking, f---, we’ve really got to make it now. It felt like a responsibility, a duty – but in a great way.

“And now I’ve let this lovely scrambled egg get a bit overdone, but hey ho, it doesn’t matter, we’re having it.”

During Lee’s development, Winslet also made heist movie Triple 9, British film Ammonite, Avatar: The Way of Water, the TV drama I Am Ruth, and the outstanding HBO series Mare of Easttown, which won countless awards, including an Emmy and a Golden Globe for Winslet, who played Marianne “Mare” Sheehan, a detective in suburban Philadelphia.

“Mare. Oh f---ing Mare. I loved playing that character so much. I loved her – she was so brilliantly disgusting.”

Of its eventual success, she says she had, in advance,“not a clue. But you never do. Even with Titanic we had not a clue. We knew the scripts were utterly compelling. I wasn’t obvious casting for Mare, but as soon as I read it, I wanted to do it. But it was spectacularly hard. I had to really become a different person – and that’s hard to do when you can’t hide behind prosthetics or some sort of costume.”

In the promotional photos for Mare, Winslet instructed the publicists not to do any retouching. “I kept saying, ‘Why have you airbrushed my wrinkles out? Put them back. I know it looks like s—t – it’s meant to.’

“That woman carried her grief in a way that affects everything – her hair, how she eats, how she moves, what she wears, how she interacts with people, how guarded she is. She will not show even a tiny bit of vulnerability because if she does, that whole house of cards will come tumbling down.

“Playing Mare was physically exhausting, and emotionally very challenging, but I have the same excitement about acting that I did when I was 17. The effervescence hasn’t left me – thank God, thank God it hasn’t.”

That effervescence is all around, as we sit outside in the garden, birds singing, dogs marauding.

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Does she think of Titanic as her sliding doors moment? “Oh yes. I am acutely aware of the opportunities that presented themselves to me because of that film.

“Back in the day, people would say to me, ‘Acting is tough – you need another string to your bow,’ and it would drive me mad, but it was completely true because in those days – a few TV channels and an occasional film – there wasn’t enough work to go around. I couldn’t believe it when I got that job. I just couldn’t believe it. Kate from Reading – what the f---?”

Kate from Reading grew up with three siblings in a terraced house wedged between Barclays bank and a takeaway. One thing she is eternally grateful for, she says, is that “I was surrounded by these huge characters. Everyone in my family was always doing a voice or a silly accent, or a show. And we were always putting on plays and dressing up and putting make-up on my brother – that was our fun.

“My mother was shy and never acted, but my dad did – though it was a terrible struggle. One day he was laying tarmac on the roads and the next he was a postman – he had all these different jobs to make ends meet so he would be free to do auditions if they ever came up, which was not very often. But I loved acting. And I probably did have drive – but it was more of a quiet determination, I think. I was never pushy. I can’t stand pushy people.”

She would look for auditions in The Stage, then got an agent and after a little bit of television, a casting came up for the film Heavenly Creatures, in which she played a leading role. Then came Sense and Sensibility, for which she won a Bafta and was nominated for an Oscar, and then Ophelia in Kenneth Branagh’s star-studded Hamlet. It was while making this that she auditioned for Titanic.

“I’ll never forget that phone call saying I’d got the part. And the first person I told was Julie Christie, which is bonkers.” They were shooting Hamlet at Shepperton, and Christie was playing Gertrude. “Julie had found a B&B close by and she said, ‘They’ve only got one room but let’s just share.’

“He’s my mate. Though we haven’t actually spoken for a while – but I’m always following what he’s doing and thinking, ‘that’s a good move’.”

KATE WINSLET ON LEONARDO DICAPRIO

“So I was sharing a bed with Julie and I’d just got a mobile phone and it was the size of a bloody brick, and at 4.30 in the morning it rang – and it was my American agent telling me I’d got the part. And I shouted, ‘Julie! Julie!’ And the two of us were jumping on the bed together – it was completely extraordinary.”

Winslet knew it was a big film because of the size of the budget, and she knew Leonardo DiCaprio’s name had come up for the part of Jack. “And I remember thinking, oh God, if only it could be him. And when the two of us got in a room together for the first time, we just couldn’t stop giggling.

“I was the grown-up, keeping us together, saying, ‘Come on, we’re going to run these lines, it’s going to be a great day.’ I was always the one rallying the troops – and I still am that person.” She and DiCaprio went on to make Revolutionary Road together 10 years later.

“And that was really special because we were older and we were able to meet each other in a totally different way, because we’d had more life experiences and more work experiences and technically we were more capable. We knew each other so well and we had the benefit of having gone through something so huge together, and also remaining really close.”

Are you still close? “Yeah, he’s my mate. Though we haven’t actually spoken for a while – but I’m always following what he’s doing and thinking, ‘that’s a good move’. He’s an absolutely phenomenal actor.”

To date, Winslet has acted in more than 40 films, narrated several documentaries and provided voiceovers for a number of animations. She was nominated for an Oscar five times before she finally won one, in 2009, for The Reader. Which roles is she proudest of? “Lee, I think. And The Reader – it was a particularly tricky time of my life so I look back on that and think, how the f--- did I get through that? Eternal Sunshine [of the Spotless Mind] – because it was an opportunity to show another set of tools from the toolbox, and I loved the film. I’m proud of Ammonite, actually – it was a challenge for Francis [Lee] to direct me as Mary Anning. He said to me, ‘Just sit there. Don’t do anything.’ Getting Kate Winslet to be still is not easy.

“I absolutely love the whole process of putting a film together and being with the other actors and director. If I’m the lead, I’m going to bring everyone with me and it’s going to be a great day – it’s about creating a tapestry. I felt so proud of Lee, and a crew member said, ‘We’re having such a lovely time. This is how it used to be.’”

Winslet is not on social media and never reads reviews. She has been judged in the press in the past, but these days she says she doesn’t care what people think. “When I was younger I did care, I really did. I was an average-sized woman suddenly in the public eye and the press commented relentlessly on how I looked, what I was eating, whether I was dieting.

“Back then, people didn’t like us to have opinions such as: why can’t women show that they’ve got cellulite and stretch marks? Why should they cover themselves up?”

KATE WINSLET

“‘Kate, looking svelte in…’ and they still do it! They still f---ing do it. They use words about women’s bodies that they don’t use about men. It’s so irresponsible. And that’s just mainstream media – I have no idea what goes online or in social media, I haven’t got a clue.

“But yes, when I was younger I was quite reactive and defensive, but it wasn’t the time in our culture to say to a journalist, ‘You can’t say that about me, it’s really hurtful.’ Because the response would be, ‘Well, you signed up for it, love.’

“Back then, people didn’t like us to have opinions such as: why can’t women show that they’ve got cellulite and stretch marks? Why should they cover themselves up? And now it sometimes moves me to tears when I see a generation of women just stepping out with pride, and completely being themselves. It’s inspiring.

“The younger generation of actors have been calling out the media for body-shaming. There is a movement now which didn’t exist before, and I have felt buoyed by that and naturally swept into it. I think my confidence evolves all the time.”

Have you ever been asked to do something in a film that you had to say no to or regretted? She thinks. “No, I don’t have any regrets. I’ve certainly had to request that something be shot in a less revealing way if I genuinely felt [like] ‘you don’t need that shot, that’s not the story we’re telling’. I’m lucky, I don’t have a problem saying, ‘Not doing that!’” She cackles.

“With a big smile on my face, I’ll say, ‘Let’s find a better way of doing it.’ I couldn’t do that when I was 18. Not a flipping chance. And I think intimacy co-ordinators are very important in our industry. It’s fantastic for young actors to have a mediator.”

She is generous about other actors. Hugh Grant is “f---ing brilliant”; Sarah Snook is “phenomenal”; and Josh O’Connor: “I’m so proud of him – he’s got the career he deserves because he’s so damn talented.” The other actor she is really proud of is Mia (who’s currently filming TV series The Buccaneers in Scotland and in the cast of Wes Anderson’s new film), Winslet’s daughter with her first husband Jim Threapleton, whom she married in 1998. “She’s so amazing. She’s a hoot.”

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Had Mia always wanted to act? “Yes, I could just see it in her but I didn’t want to say anything – you don’t want to plant a seed. So I just kept my mouth shut and when she told me she wanted to act, I said, ‘OK, cool.’ And she said, ‘You didn’t think I was going to say that, did you?’ And I replied, ‘I’ve known you were going to say this since you were about two. Go on, then. Off you go.’”

Her son Joe (with director Sam Mendes, to whom she was married for eight years) also acts. In 2011, Winslet and her children were on Necker Island when a storm struck and the house she was staying in was hit by lightning and caught fire. They got out, with only their passports, helped by Richard Branson’s nephew, Ned Rocknroll, whom she had met a couple of days before. “It was very clear to me,” she says now, “that this was the person I was supposed to follow through life. And I still feel exactly that way now.”

In tribute to how they met, their son Bear’s middle name is Blaze. What does Ned do? “He looks after everybody. He’s wonderful. We literally do life together, we really do. He’s always jumped from project to project, and when I met him he was setting up a music festival.” She didn’t know that his surname was Rocknroll (he’s now changed it back to Abel Smith).

“When someone told me, I thought, that’s brilliant, because the funny thing is, he’s not remotely rock and roll. He’s Mr Vegan Yoga. He’s just the life and soul. Ned and I, we are real-life optimists. When you live with someone who wakes up, opens the curtains, and says, ‘Hello, the world!’ you just think, yes, I am going to sign up for life.”

Lee will be in cinemas on October 24.

The Telegraph Magazine, UK.

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