Sienna Miller pushed her director to make her not just 'the wife' in her new movie

Sienna Miller GettyGettySienna Miller.

One thing actress Sienna Miller has a lot of experience in: playing the grieving wife.

“The Lost City of Z” (opening nationwide on Friday) marks the third time in three years that Miller has played a homemaker who has to deal with extraordinary circumstances. But with “Z,” she pushed for her character to have a more substantial role in the film — and it paid off enormously.

In the acclaimed and Oscar-nominated films “Foxcatcher” and “American Sniper,” both based on true stories, Miller played the wives of men who tragically died — David Schultz and Chris Kyle, respectively. In both instances, Miller, while unquestionably talented, has blink-and-you’ll-miss-it parts that really only serve as emotional triggers when the husbands are murdered.

The same could have happened to Miller in “The Lost City of Z,” playing another real woman, Nina Fawcett, wife of British explorer Percy Fawcett, who along with their son disappeared looking for a secret city deep in the jungles of the Amazon in 1925. But writer-director James Grey gave the Nina character a rich inner life that highlights her struggle to support her husband’s obsession, which then leads to the eventual torment over never knowing what happened to her love and eldest child after they disappear.

But Grey admits that credit should also be given to Miller, who urged him not to just go through the motions with the Nina character.

“When she arrived in Northern Ireland I remember we had the table read with all the actors and she wrote on the side of the script, ‘The wife?!’ And I said, ‘What do you mean by that?'” Grey recently told Business Insider. “And she said, ‘I’m just playing the wife again. Don’t you think we can do much better?’ And I said, ‘Sienna, I’m going to try. I’m going to give you everything I got.'”

Lost city of z amazonAmazonSienna Miller in ‘The Lost City of Z.’

Miller does not disappoint with the material, delivering one of her best performances in recent memory. It’s more than obvious to Grey that she had a chip on her shoulder.

“At one point I said to her, ‘I don’t understand, if you think you’re just the wife, why are you here?’ And she said, ‘I wanted to work with you, and that’s why it has to be better. Better than the average woman left at home,'” Grey said, delivering his best imitation of Miller’s English accent.

After filming, Miller told Grey at the premiere that she based a lot of her performance on watching Grey’s wife during production. He had had no idea.

“She told me she was copying my wife’s gestures and behaviour and attitude,” Grey said. “I don’t know how my wife feels about that.”

However, looking back on it, Grey said the Nina character was one of the most important aspects of the story.

“It’s Nina’s tragedy,” Grey said, referring to the loss of her husband and son. “She never heard what happened, no closure. It’s the 1950s and she’s still alive and people say they have seen him. So I thought if that’s the case, the movie can’t forget about her.”

And what does Miller think of the movie?

“Oh, she loves it,” Grey said.

NOW WATCH: Warner Bros. might have to pay $US900 million if it can’t prove ghosts are real

NOW WATCH: Briefing videos

Business Insider Emails & Alerts

Site highlights each day to your inbox.

Follow Business Insider Australia on Facebook, Twitter, LinkedIn, and Instagram.