Noomi RapaceandJoel Kinnamanare no stranger to dark, intense roles.

But both acclaimed actors callThe Secrets We Keepthe most difficult project they’ve ever filmed.

“I have to say, it was the toughest shoot Ive ever had,” Kinnaman tells EW.

The Secrets We Keep

Credit: Bleecker Street Media

“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.

The Secrets We Keep

Patti Perret/Bleecker Street Media

“I had terrible nightmares.

“Ive had my fair share of torture.

But the emotional toll of this was so high.”

The Secrets We Keep

Patti Perret/Bleecker Street Media

“And then because youre bound so tight, you cant untie in between takes.

I had to sit on that chair, bound for hours.

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.”

“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.

‘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.'”

“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.

She credits the director and her costars with helping her carry the burden of Maja’s trauma.

“It made it possible for me to stay in the pain, in a way.

I didnt 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.

Hes 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.

“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.”

“Ive done a lot of films but this was so important to me to tell this story.”

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