Bill Skarsgard will do anything for Stephen King. So when the actor, who also famously took on the role of Pennywise in It, landed a part in Castle Rock, he went to the extremes. Playing a character who is found after living in solitary confinement, he knew he had to get into that headspace – and get the look down.
“I wanted to lose weight because I wanted the character to be more gaunt and ghostlike and malnourished and look weak,” Skarsgard, 27, told Us Weekly exclusively at San Diego Comic-Con. “I basically did the Keto diet. You get into ketogenesis and you just eat a lot of fat and no carbs. I lose weight quickly. Before scenes, I would not drink water or eat for 24 hours. It does a lot … It changes your face. I think it played real well into the role. It gave off this boney, skeletal look.”

He also noted that during filming, he did have cheat days – and there was one meal he couldn’t wait to have after they wrapped.
“We shot a scene in the shower at block five. Even though it was episode one, we shot while shooting episode five so I’m like, ‘Well f–k, I need to stay skinny all the way up to the point,'” Skarsgard explained. “I didn’t eat for 24 hours. The day before, 24 hours before that, I had like, a salad and didn’t drink any water. So I was f–king skinny and parched. Then after that day of shooting, I wanted a beer and burger. I didn’t drink for three months, either, so I went to a shady dive bar and it was great.”
Castle Rock premieres on Hulu Wednesday, July 25.
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