‘The Staircase’: How Colin Firth Changed His Acting Approach to Play Michael Peterson

The series debuts on HBO Max Thursday

Colin Firth stepped outside of his comfort zone for his latest role as Michael Peterson in HBO Max’s “The Staircase,” premiering Thursday night with the first three episodes streaming on HBO Max.

The limited series, based on a true story, follows the mysterious circumstances surrounding the death of novelist Michael Peterson’s wife, Kathleen Peterson (played by Toni Collette), who was found dead at the bottom of the staircase in her home in December 2001. Michael was later convicted of her murder. He has maintained his innocence, successfully appealing for a re-trial before eventually taking an Alford plea (allowing him to accept his sentence without actually admitting guilt).

Prior to his turn as Michael for the HBO Max show, Firth had approached many of his previous roles in a similar fashion, he told TheWrap.

“I suppose I’ve always assumed in my work that you try to get to the heart of a character and that there is a heart,” he said. “I don’t mean in the sense of having a big heart or [being] heartless. I just mean that there’s a core and that I will try to get to it, and that will be somehow a kind of base through which whatever nuances I can find come from, and I can return to and be planted in it.”

Playing Michael, though, presented new challenges, Firth said.

Across the series, perceptions of Firth’s character are constantly shifting. Family, friends, and even Michael’s lawyers — who at first believe he would never commit such an act of violence — begin to question his innocence.

“I didn’t know if Michael Peterson’s presentation of himself was going to be helpful to me in terms of finding out what lies underneath and I found that it kept sort of moving,” he said, adding that the role led to a larger realization about his acting approach.

“I wondered if, perhaps, I’ve been over simplifying all these years. Perhaps there isn’t just some fixed core to characters, that maybe that’s a sort of conceit that I found, rather conveniently useful as an approach — that maybe everybody’s somewhat elusive and changeable and multifaceted and hard to nail down,” he pondered. “So in some ways, this was a very, very palpable example of human elusiveness and unfathomability.”

In addition to Firth and Collette, the scripted show also stars Michael Stuhlbarg as Michael Peterson’s defense attorney David Rudolph; Patrick Schwarzenegger as Michael’s son Todd Peterson; Dane DeHaan as Michael’s other son Clayton Peterson; Olivia DeJonge as Caitlin Atwater, Kathleen’s biological daughter; Sophie Turner as Margaret Ratliff, one of Michael Peterson’s adopted daughters; and Odessa Young as Martha Ratliff, Michael’s other adopted daughter.

New episodes of “The Staircase” drop weekly on HBO Max.