This weekend, a new modern take on Stephen King’s Carrie opens in theater. Chloe Grace Moretz stars as Carrie White, the girl with telekinetic powers who gets teased by the high school mean girls. The new film follows the same story as King’s book and previous films, culminating in a prom night prank that sets Carrie off on a reign of terror. Moretz recalled shooting the fateful scene where she is covered in pig’s blood.

“At the end of the day, I was just the actor who had to stand there and get it dumped on me,” Moretz said. “They did something like 50 or 60 or 70 blood tests with one girl dropping the blood every day, five times a day to try and figure out, what height, what air pressure. Do they drop it from a real bucket, or do they use the compressed thing? What gives you the best splatter, different types of blood?”

They had to get it just right, because once they were filming, it was too messy to film multiple times. “They had two takes,” Moretz said. “We had the first take one night, and then another night to do it, but one take. So that's all they had for that entire blood drop. So for them, they were going, ‘If we don't get this right, we're done.’ If we don't get that first setup right, we can't do it again so you're screwed. If it misses your head, then we don't know what we're going to do because it's like a four hour turn around.”

Moretz had confidence that the filmmakers, led by director Kimberly Peirce, would get the technical parts right so she could just act in the scene. “For me, just being able to walk on set and be like super chill and like, ‘Cool. Whatever happens, happens. I'm good, guys. Don't worry about me’ because they were all so stressed out.  My only thing was I don't want to see anyone counting one, two, three. I don't want to hear anything happening. I just want to be completely in the moment, smiling, happy. I just won Prom Queen. And just whatever happens, happens.”

The blood did fall just right, and then it was up to Moretz to continue the scene for Carrie’s rampage. “What was hard was knowing that after the blood hits, then have to keep going on with the scene. So we didn't just go, oh, blood hits, cut, we're done. It was like: blood hits, then follow it through for like five minutes and do the entire scene until Tommy gets hit in the head which is really long.”

Despite all the tension of setting up that shot, Moretz and costar Ansel Elgort had to release it once Peirce called cut. “It was so funny because after that first blood drop, Ansel and I looked at each other, and we were just like started cracking up. We were like hugged each other, and everyone gasps because our blood like got all over each other. Then he just like slipped and fell right on the ground and then I was slipping, and it was ridiculous, but it was cute.”

Carrie opens Friday.