Evan Peters had to go to a dark place to play the infamous serial killer Jeffrey Dahmer and he needed a little help from one of his Netflix co-stars to return to the light.

In a cast interview shared by the streaming service on Monday, the star of Ryan Murphy s controversial Dahmer Monster: The Jeffrey Dahmer Story revealed how difficult it was both to get into character and to shake it all off.

I put in so much negativity and darkness to portray the character that I thought, OK, once this is done, all of that goes away and I have to get back into the light and start filling myself back up with comedies and romance and sorts of things like that, Peters said Monday.

One of those comedies was the 2008 film Step Brothers, featuring none other than his Dahmer cast mate Richard Jenkins.

In preparation for his Dahmer role, the 35-year-old Peters said he watched as much as I could of the notorious murderer, including courtroom footage.

He has such a distinct voice and that dialect, Peters said. I worked with dialect coaches and then created this 45-minute audio composite that I listened to every day to stay in the accent, but also to really get into the mindset for the day and all the scenes we were shooting.

The series became one of Netflixs most viewed ever after it debuted in late September, garnering both acclaim and criticism for its accuracy. The real-life Dahmer, known as the Milwaukee Cannibal, murdered 17 men and boys from 1978 to 1991 mostly Black and gay and ate some of their corpses. He died in 1994 after being beaten in prison.