Matt Bomer has gone to dark places in “American Horror Story” and beyond, but his role on “The Sinner” pushed him to a totally different space.

“This is the most challenging role I’ve had, but it’s also the most rewarding as an artist,” Bomer told Variety at the show’s Season 3 premiere Monday at the London in West Hollywood. “It asked the most of me and demanded the most of me … It definitely took a psychological toll, a physical toll, but I think that’s what you hope for as an actor.”

In this season of the dark thriller, executive produced by Jessica Biel, Bomer plays Jamie Burns, a man thought to be a model citizen of Dorchester, whose secrets start to come to the surface after a deadly car accident.

“[Series creator] Derek [Simonds] wrote this really three dimensional character. All the way until the end of the season, I didn’t know the next turn this character was going to take,” Bomer said. “I was waiting with bated breath.”

As for how he let go of the heaviness of the role off-set, Bomer laughed, “I burned some sage. When I was done, did a few little rituals, washed it all off and then went home and tried to be a parent again and a husband.” The actor also shared that he leaned on Biel, who came to set often, for support.

“She’s phenomenal,” Bomer said. “She was there from the get-go, before this even started. We sat down, we had lunch, [Biel’s co-producer and Iron Oceans co-founder] Michelle Purple was there. She and I talked about the show, what the tone was, and what to expect over the course of the season.”

He continued, noting that most actors on the show have to assume dark roles, “I always say there should be like a ‘Sinner’ support group for everybody who has had to play the sinner because you can’t really understand it unless you’ve had to do it. It’s that dark. And [Jessica] has, and she was always there for me to lean on. … She’s a great boss.”

As the premiere began, Biel stood in front of the audience to thank everyone for coming. “I’m so excited to still be somewhat a part of this show,” she said. “This has been such an amazing experience for me, and I’m so thankful to everyone who continues to make this show so incredible. Everyone has done such insanely strong work this year. I’m just blown away. I’m so grateful. The season is so unique. It’s so different.”

Joining Biel and Bomer for the screening were season three stars Bill Pullman and Parisa Fitz-Henley, as well as Biel’s husband Justin Timberlake. Following the screening, attendees headed to a reception where they mixed, mingled, and sipped themed cocktails like Buried Secrets and Gin & Sin.

“The Sinner” Season 3 premieres Thursday on USA Network.