The First Omen Star Nell Tiger Free Says Her Dad 'Nearly' Fainted Seeing Her Horror Movie (Exclusive)

Nell Tiger Free's parents got quite the scare seeing her new horror film The First Omen.

The Servant actress, 24, tells PEOPLE that her mom and dad supported her by braving the shocking new film, in which she plays a young nun uncovering a dark plot.

"My mom does not like horror films — she's very, very squeamish — so she had to sit next to me at the premiere," says Free. "And I swear to God, I think I have nail marks in me. She was gripping onto me so tight the entire time."

As for her father, Free explains that he "fainted" during her birth ("He's a diabetic. He needed to sit down and have a Mars bar. My mom was like, 'Really? Right now, while I'm giving birth? Seriously?'"). Seeing The First Omen, he "nearly" fainted as well, Free jokes.

Free, also known for Game of Thrones, says her mother "cannot handle ever watching anything bad happen to me."

"I've had to have a lot of bad things happen to me on screen. I've been shot in the head, I've been burned alive, a lot of stuff," she says. "So with this one, especially in those final scenes, she was really struggling with it."

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Still, her family has been "so supportive and lovely and wonderful, as they always are."

Even her horror-avoidant friends were able to make it through The First Omen, which is a prequel to the 1976 classic The Omen.

"It's my favorite genre, to be honest with you, horror is. I'm always trying to make my flatmates watch horror films with me, and they're not horror fans," says Free. "They actually came to the premiere and they were like, 'We're doing this out of love for you,' but they really enjoyed it, which is good news."

Does anything scare Free in real life? "A lot" does, she admits, including clowns.

"I'm terrified of clowns big time. I was chased by one in London once. And I was already terrified of them then, and that just solidified it for me," she says, adding, "I'm scared of the open ocean, open water. I've also recently learned, thanks to TikTok, that I'm scared of giant objects being submerged underwater."

She says, though, a mantra she learned from her dad, who calls her the nickname Noodles, keeps her feeling courageous every day.

"When I would get nervous when I was little," says Free, "my dad would always be like, 'Be fearless, Noodles. You're fearless.' He made me repeat it often, and say, 'I am fearless.' I find myself with that being a little bit of a mantra, like I'm trying to convince myself that it's true."

The First Omen is in theaters Friday, April 5.