Colin Firth (Pride and Prejudice, Mamma Mia) will be appearing in HBO Max’s upcoming limited series, The Staircase, in the spring, according to Deadline. He has since spoken out about his preparation for the role.

The eight-episode series – based on a true story – follows Michael Peterson, played by Firth, who was convicted of murdering his wife Kathleen, played by Toni Collette (Hereditary). He claimed Kathleen died from falling down their stairs, but his charges were later diminished to manslaughter after new information came to light proving that one witness for his prosecution gave a misleading testimony.

“I didn’t communicate with Michael Peterson,” Firth said in an interview Tuesday. “I felt the way the script was structured and just the whole approach of this was its own ecosystem, so to speak. These are created characters but we all know what the source is. We all know that these characters have names of living people, but it’s very carefully calibrated to tell the story in a certain way. I felt that I wanted to keep my inspiration, my motivation, and the sense of the source material, as much as possible contained within the script and the way it was written.”

Firth added that he felt that any form of personal connection to his character would have impacted his portrayal.

“I felt that that could have been skewed in some way if I had personal connections, during the shooting of this, with Michael Peters and other people concerned,” he said. “If I’d had a personal response to the meeting, it might have prevented me from tuning into this world of varying possibilities that had been created.”