Noomi Rapace and Joel Kinnaman on why filming The Secrets We Keep took a heavy toll

Noomi Rapace and Joel Kinnaman are no stranger to dark, intense roles. Rapace shot to fame for her deeply inhabiting the title role in the Swedish Girl With the Dragon Tattoo film adaptations, and Kinnaman regularly loses himself in dramatic fare like The Killing and Hanna. But both acclaimed actors call The Secrets We Keep the most difficult project they've ever filmed.

The post-WWII revenge thriller directed by Yuval Adler stars Rapace as Maja, a Romani woman who is rebuilding her life in the suburbs with her husband (Chris Messina) when a chance encounter leads her to the man, Thomas (Kinnaman), who she believes brutalized her and her family during the Holocaust. She kidnaps him and seeks vengeance for the heinous war crimes she believes he committed against her, altering all three of their lives forever.

"I have to say, it was the toughest shoot I’ve ever had," Kinnaman tells EW. "It was emotionally and physically exhausting to the point where I thought I was losing my mind. This is one you really want to be worth it."

And bringing Maja's story to life onscreen began affecting Rapace physically offscreen. "It moved into my own body and I was very stressed," Rapace, who also executive produced the film, tells EW. "I had terrible nightmares. I was out walking a lot, I tried to meditate, I did ice baths, I was getting head massages to release all this tension in my body."

Kinnaman knows that his history of "really intense roles" should have prepared him for this project, but "the emotional impact" it had on him surprised even him. "I thought I had done so many dark roles and projects before but I did not expect this to affect me in the way that it did," he says. "I’ve had my fair share of torture. But the emotional toll of this was so high." The actor recalls "being tied up for hours on end" because the director "stressed that this film lived and died in feeling that the torture is real." Kinnaman chuckles as he calls Adler "a tough cookie," and admits that while he "agreed with everything [the director] did," not being able to escape from his shackles for hours having his mouth gag in all day long was the most method he's ever had to go while filming, and he didn't appreciate it at the time.

"Everything was bound so tight that I literally was bleeding from my arms from the ropes and I had cuts in the corners of my mouth from the mouth gag," Kinnaman says. "And then because you’re bound so tight, you can’t untie in between takes. I had to sit on that chair, bound for hours. Intellectually I knew we were making a film and this wasn’t real and that none of this is really going to be dangerous to me, but the body doesn’t really understand that. Your body is just experiencing this abuse and it just created this emotion in me. The whole shoot I was going around filled with this desperate rage that was bubbling under the surface."

No matter what set he's on, Kinnaman prides himself on his ability to create "a warm and generous spirit" for the other cast members and crew. "That's really important to me, regardless of how intense the work is," he says. "And I had zero energy to do that for this. Actually it got pretty heated – me and Yuval got in a lot of fights. We were screaming at each other on set. Usually, when I’m done with a performance I’ll thank the crew but here it was more of an apology."

But it's not just Maja's actions and torture of Thomas that took Rapace to a dark place; it was also exploring the character's long-buried trauma that not even her husband knows exists. When she kidnaps their neighbor, it is the first he's hearing of her painful past, and the question of whether he believes her that the man tied up in their basement is actually a war criminal adds another layer to the already explosive situation.

"That's the brutality of someone who has been raped, or something terrible happened to them, and then they are not being believed; it's almost like a double rape on top of it," Rapace says. "Getting into the emotion and going as far as I can into the character, I felt so lonely some days and like I was in the eye of a storm trying to prove my point. 'This sounds crazy but I'm not crazy!' And that makes it even more painful. 'I can't prove it, but I know what I saw.'"

Maja's own memories of that fateful night 15 years ago are cloudy from time and PTSD, and watching her own husband question her sanity is agonizing for both the character and viewers. "It's so important to believe if someone tells a story about an abuse," Rapace says. "It's very rare that it's a made-up story. A lot of victims actually tone it down because they feel guilt and they feel shame and it's quite common that you blame yourself. And for Maja, she actually starts using her voice and standing up for what happened, and then she's not being believed; it almost became torture."

Patti Perret

She credits the director and her costars with helping her carry the burden of Maja's trauma. "Some days when I felt like I was drowning, Chris Messina just came and hugged me and was holding me and gave me so much love and support, and so did Yuval and Joel," Rapace reveals. "It made it possible for me to stay in the pain, in a way. I didn’t need to shut down and protect myself because I felt protected in the group." Laughing, she then adds, "Chris Messina is just a f---ing blessing to work with. He’s a happily married man but during the production, we truly became a couple, a partnership."

And Kinnaman credits Rapace with helping to keep him focused and sane throughout filming. "We actually went to the same high school together in Sweden and have known each other since we were little and have been wanting to do something like for a long time," he says. "Doing these things with someone like Noomi, she goes there. We had these long theater-like scenes and it just felt so real when we were doing it. It was actually eerie. It was surreal at times."

Despite how difficult a project this was for all involved, Rapace says that it's actually the one she's most proud of for many reasons — including helping to bring awareness to the persecution of the Romani people. "It's my responsibility as an actor and as a producer to tell stories that are untold and to use my power and voice to shine light on unspoken things," she says. "When I did Sherlock Holmes with Guy Ritchie years ago I played a woman of Romani descent and I remember me and Hans Zimmer, who did the soundtrack, had a really long conversation about the Romanis and how badly treated they are. Even today they have a very bad reputation, they are being chased away, they don't have rights, they're a very torn and tortured people."

Rapace found it "disturbing" that she hasn't seen that depicted in films, so she knew she had to. "It’s been a people that my heart beats very loud for, for a very long time," she adds. "I’ve done a lot of films but this was so important to me to tell this story."

The Secrets We Keep is now playing in theaters and on demand beginning October 16.

Related content: