Saoirse Ronan considers cold water swimming to be her "safe space"

Speaking to the BBC, Saoirse shared: "That's something I love to do - I've swam in cold water since I was a kid in Ireland. It's kind of my safe space."

Saoirse found shooting the drama movie to be "an incredibly immersive experience".

The actress explained: "Everyone got involved, in front of the camera and behind the camera, in what the lead character was experiencing.

"So every time we would go out on a boat, or film the seals and I would sing to them, everyone would get involved.

"We'd all wild swim together, we all lived together. It was an incredibly immersive experience."

Meanwhile, Saoirse previously admitted that it would be easy to be "consumed" by her own fame.

The acclaimed actress acknowledged that success can easily change people.

She told the Irish Times newspaper: "You need to be a secure enough person. And you need people around you to say: 'Remember who you are.' It's easy to get wrapped up in it. To get consumed by it."

Despite this, Saoirse feels she's been "protected" from the pitfalls of fame and success by her family.

The movie star said: "I think I was protected.

"I have worked with great producers. There are some that will take advantage if they can. I don't even mean sexually. I mean they'll get you to work overtime if you're a child. They'll not protect your safety if you're in stunts or in scenes that could turn sexual.

"But my mam was brilliant. Everyone loved my mam. She was always fiercely protective of my rights."