Toni Collette, who plays murder victim Kathleen in “The Staircase,” revealed that the cast went back and forth over who was to blame for her death. “During the shoot, we changed our minds every second day, and that’s part of the retelling of it,” Collette told Variety. “That’s part of why it’s so compelling. We’ll never actually have an answer. I don’t know.” In real-life, Peterson was convicted of first-degree murder in 2003 and sentenced to life in prison. However, a judge vacated the verdict in 2011 after it was revealed one of the prosecution’s witnesses had allegedly lied under oat. Peterson was later released from jail in 2017 for time served.
Star Firth explained that his portrayal of Peterson hinged on a “maze-like trajectory” of miniseries storytelling. “This obviously draws on the story with which we think we’re familiar. But despite that, it’s a construct,” Firth said, adding he did not seek out the real-life Peterson to prepare for the role. “It’s lovely fiction, and I think I found it more helpful to stay within the parameters of what was written.” Firth shared that even fans have tried to deconstruct his eerie portrayal of Peterson in attempts to uncover his supposed personal bias. “Earlier today, somebody said she watched it looking for clues in my interpretation as to what I thought: ‘There’s this expression, or that moment. Does that deliberately mean that Colin thinks that?’” Firth explained to Variety. “I think it would be a shame to answer that, because I think this thing is specializing in making you question, and being honest with the fact that we can only speculate. We can only guess. You can gravitate towards whatever certainty.” The Oscar winner added, “But I think that this is playing with varying possibilities. And I think it would be a pity having gone to all that trouble to have the actor say, ‘I think this happened.’ Get back to me in a few years when everyone’s seen it.” Co-star Parker Posey similarly shared with The New Yorker that the cast couldn’t stop talking about the real case. “Every weekend, we got together and talked about [whether he did it],” Posey added. “You go up and down the staircase, and think, Is he guilty? Is he innocent? Did he do it? Did he?” Sign Up: Stay on top of the latest breaking film and TV news! Sign up for our Email Newsletters here.