LOS ANGELES, July 29 (UPI) — Rupert Grint said his new horror movie Nightborn, premiering Friday on Shudder, reflected his fears about his own children. Grint found out he was having a second child before filming the movie in Finland.

Grint plays Jon, a new father restoring a house in the Finnish woods with his wife, Saga (Seidi Haarla). Baby Kuura, however, is a bit of a monster.

In a recent Zoom interview with UPI, Grint said he already has plenty of fears of his own about being a good father.

“Being a dad myself, it was very triggering, I think,” Grint said. “It’s such a scary time, letting this creature into your house. It does sometimes feel like an alien. There’s lots of strange things you have to learn on the fly.”

Nightborn is Grint’s second horror project involving a child. Apple TV+’s Servant cast Grint as the brother of a woman (Lauren Ambrose) using a realistic doll to cope with the death of her child.

“It reinforced that it’s a terrifying thing,” Grint said. “You’re so anxious all the time about this precious creature but I think what this script does really well is tell that honesty of what it’s really like. It’s not all a beautiful time. It can be very gruesome and hard.”

Kuura has body hair in unusual places and develops a taste for blood. Still, Haarla did not feel Saga’s struggles were far-fetched.

“For me, it was an exploration of motherhood, maybe the shadow side of motherhood,” Haarla said. “I tend to think that everything can be real maybe, but I felt it was a real exploration of motherhood and a mother/baby connection and bonding.”

Writer/director Hanna Bergholm, who co-wrote with Ilja Rautsi, said the story was inspired by her own observations about motherhood “and also about the changes that might happen for women, especially in women’s bodies and how to deal with that. You might say that the story’s also about how to face yourself as you are and with all your uncertainties and fears.”

Kuura’s name and monstrous qualities did have root in Finnish myth. Otherwise, he is Bergholm’s own creation.

“Kuura means frost in Finnish language so it’s kind of a nature world,” Bergholm said. “Yes, we do have old Finnish mythology of trolls living in the forest.”

Saga’s mother and sister come to visit and they are full of ideas for how to help Saga with Kuura. Kuura defies their know-it-all advice.

“This film is also about this miscommunication between people and how different people see things differently,” Bergholm said.

The miscommunication drives Jon and Saga apart. Saga does not appreciate Jon telling her how to handle a newborn.

“It all comes from a good place,” Grint said. “He’s definitely trying and always kind of saying the wrong thing, never quite communicating in the right way.”

Haarla gave Jon a bit more credit. He was astute that Kuurla was hurting her as she toughed it out.

“Jon was right,” Haarla said. “Jon actually saw that you are in pain and you are crying inside and lying that everything is fine. It’s so small but crucial stuff that when we make the mistakes of not being able to be honest to ourselves and to each other and then stuff starts to go wrong.”

A fight between Jon and Saga required weeks of choreography before filming. Grint said that brought the actors closer together, even though they were rehearsing the ultimate conflict.

“We really got close and intimate,” Grint said. “It was violently physical. It was a great way of getting to know each other and feeling out that relationship and how we move. It was something I’ve never actually done before with a character.”

Kuura himself was often an animatronic model puppeted by five puppeteers. Babies of different ages were used as Kuura grows up.

Prior to Nightborn, Grint has found himself in several horror/thriller projects like Servant, A Knock at the Cabin and an episode of Guillermo del Toro’s Cabinet of Curiosities. He says he liked exploring the genre.

“It gives you so much freedom,” Grint said. “It’s such a fun place to play. I’ve always really enjoyed it. This was a great experience and also very international. I loved being in a different place, a different culture.”

Nightborn is technically Haarla’s first horror movie. However, she said she finds horror in everything.

“I find scary stuff in every project I do,” Haarla said. “I think that horror exists everywhere but in this genre, this was first.”