For Daisy Ridley, acting can be exposure therapy.
“I don’t like the open water,” says the star, 32, who nevertheless stars as ocean-swimmer Gertrude “Trudy” Ederle in Young Woman and the Sea.
“I knew that I would have the support necessary to train, and I knew I would mentally be able to overcome it,” Ridley tells PEOPLE, adding, “even though it was difficult.”
Ultimately, her choice to produce and star in the Disney biopic from director Joachim Rønning, writer Jeff Nathanson and producer Jerry Bruckheimer boiled down to a simple reason: “I loved the script, it’s one of those things. Really, I wanted to be part of the story so much that even with the fear, I knew I wanted to try.”
For the Star Wars actress, this is not the first time desire has outweighed fear in pursuing a role.
“Oftentimes, I’ll read something and think, ‘We can deal with the difficulties later.’ I did an action film before Christmas, and I loved the script, but I have become scared of heights, and a lot of it is at height. And I thought, ‘I’ll deal with this later!’ ”
Young Woman and the Sea is based on a remarkable true story: on Aug. 6, 1926, Ederle became the first woman and fastest person to successfully swim the English Channel. As the movie makes clear, the Brooklyn-born Olympic champion overcame significant odds to complete her historic trek — not only the treacherous 21-mile crossing from France to England, but the pervasive gender discrimination of her time.
“Nobody’s ever heard of this girl, she disappeared in time, and that’s one of the reasons we made the movie,” Bruckheimer, 80, tells PEOPLE.
Most audiences today “don’t understand that journey, how women were treated, how men felt about them. They felt that they should be in the kitchen making babies and not in the water swimming.”
As an actress, of course, it was recreating Ederle’s groundbreaking feat that most challenged Ridley.
Before signing on to Young Woman and the Sea and training with seasoned swimmers, Ridley “had never done a full length of the pool,” she told The Hollywood Reporter earlier this month. “I feel like, generally, the stuff I learned for Star Wars is transferable.… But swimming is just a different thing, so it felt like really starting at the beginning.”
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Speaking to PEOPLE, she says there was no fakery in the movie’s sequences, filmed in the Black Sea, depicting Ederle shivering in the open ocean.
“It’s unusual to do something that’s so rigorous and physically heavy, day after day after day,” she recalls of having to “really steel myself” to get back in the water after breaks. “That was really the biggest mental hurdle, to overcome that.”
Young Woman and the Sea, in theaters now, also stars Tilda Cobham-Hervey, Sian Clifford, Jeanette Hain, Kim Bodnia, Christopher Eccleston, Glenn Fleshler and Stephen Graham.