(Spoiler alert: Please do not read ahead unless you’ve seen all of “American Horror Story: Cult.”)

If you were shocked watching Kai (Evan Peters) strangle the life out of his sister Winter (Billie Lourd) toward the end of “American Horror Story: Cult,” so was he. Well, Peters was. In fact, TheWrap got to watch the “AHS” alum react to himself choking his co-star in a recent interview for our Emmy Rewind series.

Peters chose this particular scene to screen with us, as it was a hard one for him to act out — and harder to view. “She’s my sister, my family, and it’s sort of taken this turn because it’s been planted by Sarah [Paulson]’s character that she’s the mole,” he says in the video above. “And I’m so crazed and gone and this point and so obsessed with this goal I mean, I’m willing to kill my family.”

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“Annnd, crack,” he added when we heard Lourd’s neck “snap” in the clip.

In the most recent installment of Ryan Murphy FX anthology series, Peters played a cult leader who slowly slips into madness while continuing to amass more followers. So mad, in fact, he, well, murders Lourd’s character.

“It’s rough watching [this] cause, like I said, it was the end of the season and just complete exhaustion and mental breakdown. I learned a lot from this season in that, I basically went too far — almost similar to what Kai is doing, which was just, you know he has this goal of world dominance.”

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“And I’m like, ‘Well, I really want to do a great job for this character and for this season, it was a current season,” he added. “And I really cared about it. I was really proud of this season and this role. So I wanted to do a great job. But I also was completely neglecting my family and friends and fiancee. And it was just really — in a way I felt like I was killing my own family. Not that way, obviously. But it was dark. It’s a crazy parallel to see it’s me actually losing it in a weird way.”

Watch the full interview above.