Sienna Miller Explains How New Show About a Highly Publicized Affair Was 'Cathartic' for Her

Sienna Miller said she was at first hesitant about her Anatomy of a Scandal role because "some of the content felt similar to moments I've experienced in my own life"

Sienna Miller. Photo: David M. Benett/Dave Benett/Getty

Sienna Miller finds catharsis acting out situations similar to her own real-life experiences.

The actress stars in Netflix's Anatomy of a Scandal as the wife of a politician (Rupert Friend), whose recent affair comes to light, sparking a media storm around their characters.

Miller — who has previously been open about her breakup with ex-fiancé Jude Law more than 15 years ago after news of his affair with his children's nanny — told ELLE U.K. about exploring a similar situation and the public attention that came with it.

"It was weirdly interesting to kind of step back in and... There is something cathartic, I suppose, about spending time in an ugly space that's familiar," she said. "And maybe reclaiming it? I don't know what the psychology of it is. But there is something where maybe you can substitute a memory with something else."

She added of that time in her life, "It feels like somebody else's existence. I can go and visit it and look at it, but it doesn't feel like my life. I can't quite believe that it all happened. And not to put it specifically on that one thing, but just the chaos of the entire decade is so far removed from my life now."

Miller, 40, said the subject matter was "familiar terrain" since her character's "feelings were familiar" in that situation. But, the character's "way of dealing with what's thrown at her is the absolute antithesis of what my way is. And so, in a kind of twisted, tourism sense, I just wanted to see how it would feel to react differently. I know that sounds weird, because you'd think it would be deeply unpleasant to sit in that space."

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Speaking with Vanity Fair about the similarities between the fictional story in the series and her own life, Miller shared, "In some ways, I was reserved about playing her because some of the content felt similar to moments I've experienced in my own life, and why would I want to put myself back into those feelings?"

"But at the same time, her reactions to the scenarios, some of which were familiar to me, were so different that I found that kind of psychologically quite interesting, how to revisit some moments and respond in different ways," she added.

Miller met Law, now 49, in late 2003 on the set of Alfie. After nearly a year of dating, they got engaged on Christmas Day 2004. Miller broke off the engagement after news of Law's affair with his children's nanny Daisy Wright went public the following year. Miller and Law separated in November 2006, but reunited in the fall of 2009 and dated for over a year before splitting again in February 2011.

Added Miller of the past scandal, "I feel like everybody's seen my dirty laundry in that department. And it also feels like another life, such a long, long time ago, and I'm proud of this work. I don't mind talking about the truth, and that is the truth."

Anatomy of a Scandal debuts on Netflix April 15.