How Toni Collette Honors Kathleen Peterson in The Staircase

Toni Collette was rightfully hesitant when it came to playing Kathleen Peterson in The Staircase.

More than 20 years have passed since the mother of five died in her North Carolina home in December 2001, and while her loved ones will never fully move on, they've done their best to go on with their lives. But with HBO Max releasing a TV adaptation of the documentary about Kathleen's death, Toni worried she'd be complicit in the opening of old wounds, telling E! News, "She was very much alive and very much at the center of this family."

Toni wanted this real-life person to be remembered for her who she was, not the grisly details of her death, and ultimately realized that a TV adaptation would do that: "Getting to know her as a person and an incredible woman is really important to the story itself."

The series breathes new life into Kathleen, Toni said, detailing the weeks and months before she died and offering a "more balanced" perspective of her relationship with husband Michael Peterson (Colin Firth), who entered an Alford plea to manslaughter in 2017. "The story just feels so honest to me and grounded," she added.

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Toni also felt that showrunners Antonio Campos and Maggie Cohn's writing captures who Kathleen was in a way that the documentary couldn't. "You would imagine a documentary would be capturing something very natural and real, but it is very much presentational in the way it's made," she explained. "If you think of someone having their photograph taken, suddenly you're a little self-conscious. And imagine these people in your home—you're not really going to get anything particularly real."

In her opinion, "Kathleen really is nothing more than a victim that's talked about in the documentary."

But the late 48-year-old was so much more than just a victim: "She was an incredible matriarch," Toni said. "She was just so capable in so many ways and so passionate and had a vital life force which, even before she died, seemed to be waning out of her through all the stress and exhaustion because she was the worker in the family."

In other words, she was like many people out there, just trying to make it day by day.

To see how Toni honored Kathleen's memory, watch the first three episodes of The Staircase, streaming now on HBO Max.

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