Playing real-life serial killer Jeffrey Dahmer was not easy forEvan Peters, but critics and viewers say the actor pulled it off incredibly well. While the series, dubbedDahmer - Monster: The Jeffrey Dahmer Story, has not been without controversy, it has seemed that everyone agrees that Peters did phenomenal with the role. But getting there was something Peters previously described as scary, and now, the actor has opened up much more on all of the efforts he’d put in to transform himself into Dahmer.

PerVariety, Peters was present for a panel for the series on Saturday with co-creator Ryan Murphy and co-stars Niecy Nash and Richard Jenkins. He explained how he was initially apprehensive about taking on the part, noting he “knew it was going to be incredibly dark and an incredible challenge.” After getting the scripts, Peters delved into months of research, starting with checking out the famous 1994 television interview with Dahmer. Murphy also said Peters wore lead weights around his arms along with lifts in his shoes to more accurately mimic the way the serial killer moved.

Lionel Dahmer and Jeffrey Dahmer in Monster

“He basically stayed in this character, as difficult as it was, for months,” Murphy said.

“He has a very straight back. He doesn’t move his arms when he walks, so I put weights on my arms to see what that felt like," clarified Peters. “I wore the character shoes with lifts in them, his jeans, his glasses, I had a cigarette in my hand at all times. I wanted all this stuff, these external things, to be second nature when we were shooting, so I watched a lot of footage.”

On getting the voice right, he added, “I also worked with a dialect coach to get down his voice. The way that he spoke, it was very distinct and he had a dialect. So I also went off and created this 45-minute audio composite, which was very helpful. I listened to that every day, in hopes of learning his speech patterns, but really, in an attempt to attempt to get into his mindset and understand that each day that we were shooting. It was an exhaustive search, trying to find private moments, times where he didn’t seem self-conscious, so you could get a glimpse into how he behaved prior to these interviews and being in prison.”

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Evan Peters Did Extensive Research for Dahmer

In the series, Niecy Nash plays a neighbor of Dahmer’s whose calls for help went ignored by the police. Nash says that when they were filming, she never really got the chance to get to know Peters, as he was so deeply entrenched in his monstrous character. When she noticed Peters was so deep into the role, Nash kept her distances while praying for him to overcome the demons that come with getting into such a dark mindset.

“I prayed for you a lot, for real, because this is weighty,” Nash said. “And when you stay in it, and you’re tethered to the material, like bone to marrow, your soul is troubled at some point. And I could see him getting tired. I just said, ‘Well, I’m just gonna make sure I keep him in my prayers, because this is a lot and he wants to do it justice.'”

Dahmer - Monster: The Jeffrey Dahmer Storyis streaming on Netflix.