Smile is well-directed and well-written, but the new Paramount Pictures horror film doesn't work without the cast. Led by a stand-out performance by Sosie Bacon as Rose, Smile is a cerebral and frightening experience that highlights questions about how people process and suffer from trauma -- all the while being a frightening exploration of a young woman's attempts to uncover more about the mysterious and malicious curse that seems to be forcing visions onto her.

Juxtaposed against Rose are the rest of the people in her orbit, like her ex-boyfriend Joel and her current fiancé Trevor (played by Kyle Gallner and Jessie T. Usher, respectively), who bring a grounding edge to the film that adds new layers to the final product. During an interview with CBR ahead of Smile's theatrical release on Sept. 30, the film's stars Bacon, Gallner, and Usher delved into the biggest surprises of making the film, how the characters perceived the plot from very different perspectives, and how tricky it can be to untangle one's self from such a cerebral horror story.

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Smile Paramount Pictures Horror Film 1

CBR: First off, congratulations on the film! It's one of those movies you want to hide from but can't look away from -- which I think is the best compliment you can give a horror film.

Sosie Bacon: That's the idea.

Smile is so psychological, so rooted in these people's psyches that I can imagine it can be hard to untangle yourselves from being in this head-space.

Bacon: Yeah, it definitely took me a while. This is the first time that I could really say that, like, honestly. I'm not very good at separating, so I think it took me a long time to get out of the headspace. You're right about that. For me, I'm just getting out of it now, a year later.

Kyle Gallner: Yeah, I mean, it was... It's hard. [Sosie] went through a lot. It was pretty wild to watch her do it. It was pretty amazing but pretty wild. I have to imagine it was hard, and then for me, personally, just my character -- he's kind of a little more... He gets to kind of step back a little bit. He doesn't have to dive as deep. He's more just there to support [Rose]... So I got off way easier. Sosie went through the wringer. She was there every second, every day, just working her ass off.

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That's a good point that you and Jessie were more removed from the actual horror at the heart of the film -- your two characters, from their perspectives, are in a very different movie than Rose, basically a Lifetime Original Movie as opposed to the horror happening to her.

Jessie T. Usher: We're doing totally different things. We interacted with those roles in very different ways. Yeah, comparatively, we're in this absolutely tragic love story.

Bacon: I mean, I've seen some pretty messed up Lifetime Original Movies.

This is a film so focused on peeling back layers of these characters and revealing their true vulnerabilities. What surprised you the most about Rose, Joel, and Trevor, respectively?

Usher: This was almost a concern of mine, at the very beginning, was the role that Trevor plays in Rose's life always comes off as if this person either doesn't care or doesn't care enough -- that he just isn't as supportive as they need him to be... I was pleasantly surprised with the way that that kind of panned out. I don't know if it was entirely all there in black and white, but by the time you've finished the movie, it felt [fleshed out].

​​Bacon: I was definitely surprised that like... I wanted it to feel real. When you're doing a horror movie, especially when you're the one that's going to be scared all the time, you really have to -- you're going to feel like kind of an asshole half the time because you're not really reacting to anyone. I think it definitely freed me up to just kind of try to just commit to it and just go full on.

Gallner: Surprisingly, I enjoyed how much subtle, funny stuff [there was]. I mean, [Sosie] definitely pulled some stuff out of our relationship, that kind of bickering couple... we mined for some stuff to try to shake it up a little because the rest of the film is so bleak.

There really are some funny moments, and I think that is so smart. It totally disarms the audience and kind of gives everybody room to breathe before it snaps them right back into the fear again. I enjoyed those moments as much as I enjoyed the jump scares and the scary moments as well, for sure.

Smile debuts in theaters on Sept. 30.