(Warning; This post contains spoilers for “American Horror Story: Apocalypse” through Wednesday’s episode.)

Kathy Bates has played several characters during her tenure on Ryan Murphy and Brad Falchuk’s “American Horror Story.” But after taking a year off for Season 7 aka “Cult,” her return for the current installment, “Apocalypse,” brought with it her most challenging role — er, roles — for the FX series thus far.

This time she’s 1) a former Mossad agent and Satanist and 2) a robot version of that former Mossad agent and Satanist, both living to serve the Antichrist, Michael Langdon, played by Cody Fern.

Also Read: All the Plot Threads We Need Tied Up in Next Week's 'AHS: Apocalypse' Finale

And, honestly, it sounds like Bates wasn’t prepared for either part.

“No. No. No. Nor did I know that I would become a Satanist,” Bates told Entertainment Weekly in an interview published Friday, when asked if she had known her robot storyline for Season 8 when she agreed to come back. “I have to tell you, when I got that script and they had me praying to Satan, I called them down to my trailer and I said, ‘Dudes, I am not praying to Satan. Cody can pray to Satan because he is Satan.'”

“But I was quite serious about it because I’m a two-time cancer survivor and I’m not gonna screw around with that! (Laughs) It’s bad enough I have to say ‘Hail Satan’ a couple of times,” Bates continued. “I know it’s entertainment but I just didn’t want to do it. But [executive producer/writer] Tim [Minear] gave me a little more information about it but it was the same as it was every year. They give you kind of a rough idea and then you get a script and go, ‘Oh my God! I didn’t know that was going to happen!'”

Also Read: 'AHS: Apocalypse' - The Biggest Questions We Have After That Wild Ninth Episode

Bates agreed this is definitely the darkest she’s had to go for the anthology series, which airs the final episode of its current season next Wednesday.

“Yeah, she’s…I don’t know if I can really describe her because she’s kind of a cipher in a lot of ways. I really plugged into the whole Mossad thing,” Bates said. “She was a killer and she was emotionless about that. She was very robotic and mechanical and still, and I think she was full of fervor and rage and all those things. But it was kinda cool to play someone as still as that.”

The “American Horror Story: Apocalypse” finale airs next Wednesday at 10/9c on FX.