Daisy Ridley was terrified of the open ocean before Young Woman and the Sea

"When I spoke with Daisy Ridley very early on, before we started… like, long before we started shooting, I said: 'Listen, I'm just gonna warn you, like, I really want to do this in the ocean,'" he said.

"I don't want to do it in a heated tank on the blue screen. I want to do it in the ocean with boats and all of that. And she was like, 'Yeah, let's do it. Like, I think the story… that's what we should do, it deserves it.'"

He continued: "Later, I found out that she's actually scared of the open ocean - like, really. And so she had to overcome that, and then she also trained for months and months open water swimming so she was as prepared as she could when we were out there.

"And we were out there for weeks, you know, in 15/16 degrees Celsius, her lips blue.

"We're exposed to the weather and the currents and it's challenging – any endeavour involving a lot of people is always going to be challenging, but when you put it on the water, it adds to the complexity of it and safety issues and all that.

"But I feel so lucky that I had her as a partner on this movie, because I doubt that anyone else could have done it the way she did it."

Veteran producer Jerry Bruckheimer also praised Ridley and explained why she was the perfect fit for the role – revealing that she had turned down other roles during the long pre-production process because she was so determined to tell Ederle's story.

"She's a great actress. You've got to start there, that's the most important thing," he said. "She's beautiful, she's physical, she's got broad shoulders, she's tall. You can just see that she could power through the water... it's not like you have some weakling in there that doesn't look like a swimmer playing the part. She was made for this movie."

He added: "And she waited for this film. She gave up other movies. So did Joachim. There were so many people that read the script, that worked as technicians on the movie that waited to get this movie made.

"They wanted to be a part of it. They felt it was such a special story and inspired them for their own kids and their own families that they wanted to see this, get out there and be a big part of getting it made."

It looks like that decision to wait could well have been a good one. Although the film was originally intended as a Disney Plus release, it test-screened so well that it was given a full theatrical release instead – with Bruckheimer explaining that audiences had responded extremely positively to Ederle's story.

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"It's the highest testing movie I've ever made – and I've have had some big hits," he said. "And so they, when they see the movie, and they watch it with an audience, it's explosive. People laugh, they cry, they applauded. They're really into this movie.

"It harkens back to all the great movies they made years and years ago, and the movies we in Hollywood made years and years ago. So it's a throwback to a great, emotional drama with humour, and it's got everything we go to movies for: it's got a big expansive canvas in the ocean and the things that happened to this girl.

"And it's this underdog story. It's inspirational. It's a girl who... she's an immigrant, she's partially deaf. Everybody is against her, including her own father, to even just get in the water. And yet she perseveres, and we want to inspire people. That's why we make movies, to make their days a little better."

Likewise, Rønning was delighted when he discovered that the film would be given a theatrical release rather than the original streaming-only plan, explaining that: "On a scale from one to 10, I would say 10."

He continued: "In this movie climate, it's so hard and it can be brutal out there. And it was something we really fought for and, you know, I just feel so grateful to be able to be here and show the movie on the big screen.

"And that's what I make movies for - not to be pretentious, but I feel that my art form is cinema. That's what inspired me when I grew up to become a filmmaker. So I'm thrilled – this is an epic story. It's epic in many ways, it's an epic emotional story. And I think movies should be a physical experience."

Young Woman and the Sea is now showing in UK cinemas.

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