The following contains minor spoilers for Control, in theaters now and on digital Sept. 27.

The sci-fi thriller Control finds Star Trek: Discovery's Sara Mitich portraying Eileen, a frightened mother who wakes up alone in a small room and chained to a metal chair. To make matters worse, she has no recollection of how she got there, who her captors are, or even her own identity. Soon enough, a voice on the speaker system demands that Eileen perform a series of tasks, or else her daughter dies. Eileen must piece together the fragments of her memories if she hopes to escape and ensure the safety of both her and her daughter.

As the tests increase in difficulty, however, Eileen is pushed to the limits, which may not be a good thing for her captors. Eileen possesses deadly telekinetic powers, and when she lashes out, little will stand in her way. Mitich recently spoke with CBR about dialing in on the necessary intensity, channeling her inner Carrie, and that bold conclusion.

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Control Back to Back

CBR: These intense, single-character narratives are almost like a subgenre in horror and thrillers. What do you enjoy about these types of movies?

Sara Mitich: For me, what I like about them [is] it's such beautiful meat for an actor that I get to play with. There's so much to explore. You can really flesh out the arcs. It's literally my face for 90 minutes. It's a wealth of opportunities to play and push myself. I find with these, as an actor, if you are not creating that character development, that arc, it gets boring. It's just you, so you have to find the color. You have got to find the different moments and differentiate, "Hey, this scene, even though it seems similar as the one before this..." The job is a bit harder, but it's a lot more rewarding. With more responsibility comes more reward. So, I love to dive in and massage everything out and really create a three-dimensional being.

Introduce us to Eileen and the set of circumstances she finds herself in.

Eileen wakes up in a room and doesn't know where she is. She wakes up in a white-padded room, in a metal chair, and she has no idea who she is. She has no idea where she is, and there's a voice telling her to do things. Eventually, she finds out she has to do these things or they are going to kill her daughter. Slowly, memories start to flow back to her as she progresses through the movie.

As you mentioned, Eileen is subjected to all these tests without having a clue what is going on or the whereabouts of her daughter. From an acting perspective, what was it like reaching those heightened levels of anxiety and panic, hour after hour?

I feel really blessed. The whole cast and crew were so wonderful and so supportive. I have a very specific process when it comes to diving into things like that. A lot of getting myself there is me walking on the set [and] talking out loud. I dive myself into it all. I am screaming sometimes, especially for those really heightened scenes with the sand and Roger. To get myself there, I am screaming. Maybe at first, I was a little self-conscious, but I just told everybody, "Hey everyone, this is my process. I am going to talk out loud. I'm not going to look at you. You can roll the cameras on my prep. You can do whatever you want, but this is what I need to do to find the truth of this."

Sure, some scenes build, and you find that breaking point mid or three-quarters through the scene. Some of the scenes start right in the middle, right at it, and there is no warm-up. You are capturing a glimpse of this person's life. If you want to see the truth of it, I have to be in the truth of it, which means no warm-up. So, my warm-up has to be before we say action.

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A lot of performers will admit that they feed off of the energy of their co-stars. You don't have that luxury. How challenging was it to carry this film without reacting against anyone else?

For the whole part in the room, there is no other living character. I got real specific to the room, to my relationship with the timer, to my relationship to the chair, and my relationship to the speaker. They all became my characters. They all became characters I played off of. The fact they weren't giving anything back, or the voice that was always giving the same thing back... That had to fuel me. I've never done anything like this. It was hard, but thankfully I had created that specificity. The nothingness, in itself, is something.

At one point, Eileen goes all Carrie on a squad of security guards. It's not very pretty. What's going through her mind?

At that point, she's in this catatonic state where she knows. There's that simple, pure knowing of who she is and what she is, that no thoughts are even necessary. Sure, there's curiosity, but now more than ever, she knows she will get her daughter back, and it's done. She could just break their necks and be simple. I think there's a reason she tortures and twists and turns. It's also been however many hours and days and whatnot. I always find it fascinating how sometimes the most powerful people in the world are so still and so quiet. That is really what I tried to dive into, just that stillness.

What kind of discussions did you have about how to convey her powers because it's done through controlled hand gestures at the side of her body as opposed to strong, bold movements?

That was all James Mark, our director. From the beginning, he said there have been so many movies that have done this. There's blood through the nose and a lot of staring and shaking of the head. We have 90 minutes of this, and there is only so much staring that I can do. He actually introduced the idea of the fingers. I did ballet for about 16 years, so my hands thankfully do really weird things, so that worked out perfectly, but that was all James from the get-go. Of course, we want to fall into the genre, but we also don't want to just be another movie like this.

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Control Red

In the end, Eileen makes an extremely difficult decision. What was your take on how things concluded?

I would have done the same thing. This is also a theme of this movie, is unconditional love above all. There is something so human and raw in having that discovery and learning what she has done -- to choose to go back, not as a form of punishment or guilt, but truly from that beautiful, selfless true unconditional love.

I didn't know where it was going the first time I read it. I wish I had a camera on me because I am pretty sure I went, "Wait. What?" It's her right choice to do. Ironically, the concept of humanity is pushed to every extreme in that moment. What is human and what isn't human? What is right and what is wrong? There is no right answer, just like in life. That ending moment -- that choice -- is one of the most human things that she does, and yet she [is] at her strongest and most inhumane part.

Audiences probably know you from Star Trek: Discovery. How has it been portraying multiple characters on one show?

Honestly, I feel so blessed. What a wonderful opportunity. It's another reason I love science fiction because it is one of the few genres you can do this. It feels very wonderful to have the opportunity to dive into the prosthetic world. I have never done that before, to create such a specific character and to be under the incredible guidance of someone like Doug Jones, who is the kindest soul in this world. Again, as an actor, I love pushing my own creative comfort-zone boundaries. How beautiful to have been able to do it in two different ways.

Catch Control Sept. 23 in limited theatrical release and Sept. 27 on VOD and digital.