Some roles take a lot out of an actor.

In an interview with BBC Radio 4’s “This Cultural Life”, Nicole Kidman opened up about one of her most difficult roles, as writer Virginia Woolf in the 2002 drama “The Hours”.

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In the film, Woolf struggles with severe depression and mental illness while writing her 1925 masterpiece Mrs. Dalloway.

“I don’t know if I ever thought of the danger, I think I was so in her,” she said of the part, which won her the Oscar for Best Actress. “I mean, I put the rocks in my pocket and walked into the river. Over and over again. I probably don’t consider danger enough.”

Kidman added, “I think I was in a place myself at that time that was removed, depressed, not in my own body.”

At the time, Kidman had only recently split with ex-husband Tom Cruise, who she was married to for 11 years.

“So the idea of Virginia coming through me, I was pretty much an open vessel for it to happen. And I think Stephen [Daldry, the film’s director] was very delicate with me because he knew that,” she continued. “I was open to understand it, which I think is probably the beauty of life as an actor.”

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Kidman also talked about how her thinking about her own mental health has changed over the decades.

“There’s a point where you’re like, oh, I have so many experiences now. I’ve delved and traversed many different landscapes of mental health and loss and ideas and joy and raised birth and you know, life is what it is. It’s far more examined for me now than when I was 14,” she said. I’m definitely in it. I’m definitely feeling it and definitely aware of the preciousness of it and the time.”

She continued, “The other extraordinary thing I’m very aware of is I’m around and exposed to some of the greatest minds in the world. I’m the recipient of their focus. I’m grown by them, I’m taught by them, I’m shaped by them, and I’m seen by them, and that is, that is a beautiful, beautiful journey to be on. I hope it still continues, but I value it. I don’t take any of that for granted and I know what it is. I try to stay in that place.”

Finally, Kidman added, “I definitely don’t want to shut down as I get older. I want to become rawer, and more open, more available and freer.”