Emily Blunt has said she gets “irritated” when she is told a female character is a “badass” as she does not feel this is an accurate description of heroic women.

The award-winning actor, 40, is set to star in Christopher Nolan’s new film Oppenheimer alongside Cillian Murphy which explores the story of the eponymous US scientist and his role in the development of the atomic bomb.

In an interview with Harper’s Bazaar, Blunt discussed the new role and her desire to play complex female characters.

“I get irritated when I’m told: ‘She’s a badass’. That’s not interesting to me because that’s not real life”, she told the magazine.

“What I like is that sense of a fish out of water, someone who’s struggling, who’s haphazardly clawing their way out.

“Women are heroic when they’re in way over their heads.”

In Nolan’s forthcoming film, Blunt stars as Kitty Oppenheimer, who she says “wasn’t an easy woman” to portray.

Kitty was the real-life wife of J Robert Oppenheimer who was known as “the father of the atomic bomb” for his role in the Manhattan Project – America’s plan to be the first to develop nuclear weapons in the Second World War.

Reflecting on what it was like to play Kitty, The Devil Wears Prada star said: “She wasn’t an easy woman – she definitely didn’t conform to the 1950s housewife ideal, and yet she found herself confined to an ironing board in Mexico’s Los Alamos, which must have driven her mad.

“I found her so interesting to play, because she was a great scientist herself, but limited by the era she lived in.

“A lot of women a few generations ahead of me weren’t allowed the juggle of a career and children – there was an expectation they should choose, and if they did choose their career, they were frowned upon.

“Even now, I see women in their 70s whose whole identity has been caught up in motherhood, and then once that’s done, there’s this sense of, well, who am I and how do I reclaim myself?”

Having spent decades in the film industry, Blunt said it could still be hard on young women who wanted to act.

She said: “My toes curl when people tell me, ‘My daughter wants to be an actress’.

“I want to say, ‘Don’t do it!’ Because it’s a hard industry and it can be very disappointing.

“A lot of people tell you not to take things personally – but it’s completely personal, especially when you’re being judged on how you look.

“So you just have to endure that side of things.”

With her face often appearing on billboards, the star said she had reached a level of fame which could sometimes cause her feelings of “dissociation”.

This could affect her two children as well, who she shares with her husband John Krasinski, known for his role as Jim Halpert in The Office.

Blunt said: “When I see myself up on a billboard, I have this complete dissociation with it … I’m like, who’s that?

“And I can see my children doing the same – they might say, oh, there’s mama, but it’s not exciting for them.

“What’s exciting for them is when I can pick them up from school and take them swimming.”

The July/August issue of Harper’s Bazaar UK is on sale from June 8.