NEW YORK — Before filming “The Forest,” Taylor Kinney not only had never met co-star Natalie Dormer, he hadn’t even watched her hit series “Game of Thrones,”

“Every time Natalie’s name would come up in a conversation, when I mentioned I was going to be doing a movie with her, people would bring up ‘Game of Thrones,’ ” said the “Chicago Fire” star.

“So I binged-watched like the first three seasons and a couple of weeks of season four, down in my mom’s basement,” said the actor with a laugh. “My mom kept yelling down, ‘Get off the couch!’ and I kept yelling back, ‘I can’t! I can’t. This is too good!’

On “The Forest” (opening Friday), Dormer stars as an American venturing into the mysterious Japanese woods where her twin sister disappeared. Kinney plays a mysterious new friend who accompanies her on the journey, and who bears little resemblance to his “Chicago Fire” character, Kelly Severide.

“Without question, he’s not Severide,” said Kinney, explaining how “the medium of film, as opposed to television, gives you a little more time to develop things.” Noting director Jason Zada — who makes his feature film directorial debut with “The Forest” — “was very open to both Natalie and me contributing ideas,” the actor clearly loved that collaborative aspect of this project.

Since “The Forest” is a horror film, it seemed natural to ask Kinney if he is a fan of that genre of filmmaking. “I really have been. When I was a kid, it was a kind of rite of passage. Things like the old Stephen King ones. I loved ‘Cujo,’ ‘Pet Sematary,’ all the ‘Amityville’ films, the first ‘Halloween’ and ‘The Texas Chainsaw Massacre.’ Those were my go-to films growing up, but then you’d need to watch an hour and a half of cartoons before you went to bed, so you didn’t freak out and have nightmares!”

Unlike her co-star, Dormer said, “I’m not a horror fan per se. My sister was the one in the family who loved horror movies. I’m more of a coward like that. But over the years, I have seen a few that I’ve liked.

“At the end of the day, I think that regardless of genre, a good movie is a good movie.”

Dormer, also known as the tattooed Cressida in “The Hunger Games,” plays twins in “The Forest” — much like Tom Hardy, recently seen playing both of the infamous twin gangsters, the Krays, in “Legend.”

“I have so much respect for Tom Hardy, because I only shot one scene with both [of her twin characters on-screen] together. That was hard enough, and surreal enough, so to have shot a whole movie, as Tom did … I have great respect for him.”

While most of “The Forest” was filmed in Serbia, Dormer did get to go to Japan to shoot some exterior scenes in Tokyo and “I did manage to go out and visit the Aokigahara Forest for one day.

“It’s a really beautiful place, a special place,” she said. “There’s so much heritage to that whole Mount Fuji area of Japan. But here’s the funny thing. I didn’t want to stray too far off the path, as the legend of Aokigahara warns you. But I did want to get in amongst the trees and take some photos.

“But here’s the thing: My Japanese driver absolutely would not leave the path. He utterly refused. So it goes to show the superstition about it being a place where people go to commit suicide is very strong for the native Japanese. They clearly respect the power of the forest.”