How to Build Psychological Horror in 15 Minutes

Locked out of a remote cabin on New Year's Eve in nothing but a bathrobe, Cleo faces a choice. She can freeze to death in the Swedish winter, or navigate something even more dangerous—the man she brought with her.

That's the premise of Sauna Sickness , a psychological thriller short that premiered at the 2026 Sundance Film Festival. It was a gem of this year's short film program that I was fortunate enough to see.

Writer/director Malin Barr tells a story that functions as both an intimate character study and a chilling examination of emotional abuse, all contained within a single freezing night.

We spoke with Barr about building tension through unreliable perspectives, the technical challenges of shooting in winter conditions on a limited budget, and the considerations she took for intimate scenes.

Sauna Sickness Courtesy of Sundance Institute

No Film School: Short films have very little time to establish characters and dynamics and build a narrative. What were the challenges you faced as you approached developing this story?

Malin Barr: I think this is one of the most fun and the most challenging aspects of writing in this format. One of the main difficulties I faced while developing this story was that the film exists within a disorienting and unreliable world. The narrative is told through Cleo’s perspective, and, shaped by her past experiences and current mental state, she is in many ways an unreliable narrator to herself. Opposite her is Tobias, who is also a deeply unreliable character, making the emotional landscape of the film constantly shift.

I was challenged to find the right entry point into both the world and the characters, one that didn’t immediately define one as a villain and the other as a victim, but instead subtly hinted at behaviors and unspoken tensions. I wanted the audience to lean in and actively try to understand what they were seeing while remaining uncertain about where their sympathies should lie.

My goal was to establish behavioral patterns that would gradually grow clearer as the film progressed, allowing the audience to recognize them at roughly the same moment that Cleo herself begins to understand her reality and, with that realization, also begin to worry for her safety.

NFS: Unfamiliar spaces feel inherently dangerous to your lead character. How did you build that tension visually as she moves through these different environments?

MB: Great question! Creating a sense of uncertainty and discomfort, both visually and narratively, was essential to building tension and the film’s unsettling atmosphere. I approached this in a few ways.

There’s a metaphorical visual element reflecting the toxic relationship: the environments themselves reinforce Cleo’s discomfort. She’s often in spaces that feel extreme, too hot or too cold, freezing outside or steamy inside—so she can never truly feel safe.

Visually, I worked closely with my DP, Malin Gutke, to develop a specific visual language for the film. We used long, wide takes to make Cleo feel small and alone, especially in outdoor spaces like the road or in the final cabin on the end, or even when entering the neighbors’ hallway, playing with the unknown space around her. In contrast, more intimate scenes used slower zooms and close-ups, creating a sense of claustrophobia, like in the sauna or during the escalating tension on the neighbors’ couch.

We also played with tempo to build tension and release. Slow, one-shot zooms heighten the unease in scenes with her boyfriend, while chaotic camera movements and quicker edits convey instability at the neighbors’ house.

Additionally, Cleo’s face is rarely shown straight on until the final moment of realization outside the sauna, deepening the audience’s sense of uncertainty and the powerlessness she experiences. Meanwhile, other characters are often framed looking down at her, lingering behind her, or crowding her—emphasizing her vulnerability in each space.

NFS: How did you approach shooting your intimacy scene, on a practical level?

MB: This was very important to me, as I come from an acting background and have personally experienced uncomfortable situations filming intimate scenes without proper support on set. I know what makes an actor feel supported and inspired, and I bring that understanding to my work behind the camera.

I spoke with my two actors well ahead of the shoot, discussing their boundaries and giving them the option to work with an intimacy coordinator. On set, we maintained a closed set in the sauna with only the necessary crew present. On set, we of course maintained a closed set in the sauna, with only the necessary crew present. We worked calmly and quietly, allowing the actors to ease into the scene. Creating a safe environment, respecting boundaries, and being clear about what the camera captures at all times are crucial for the actors to feel free and confident while exploring the scene.

NFS: Jim Cummings came on as executive producer. How did that relationship come about, and what did he bring to the project?

MB: I met Jim when he cast me in his film The Beta Test , and since then, he has become a close friend and collaborator. I had admired his work long before we met, and it’s been incredible to be around and work with someone so creative, talented, and hardworking. During the development of Sauna Sickness, I often bounced ideas off him and Julia Bales, his equally talented and amazing wife. They helped me with everything from script notes to filming applications and fundraising advice.

In post-production, Jim was just a rock and helped me with any issues or questions that came up, from editing notes, technical questions, credit design... he even did some VFX! I'm telling you that man really can do it all, and having such a supportive, inspiring friend, collaborator, and community has been invaluable to me and the project.

Sauna Sickness Courtesy of Sundance Institute

NFS: What's one thing you learned making this short that you're going to apply to your next project?

MB: One thing I learned making this short is: never try to shoot something set in winter unless you have a huge budget. Even though we went far north in Sweden to a snow-safe location, climate change is real, and it turns out to be incredibly challenging to spread out fake snow!

I’d also love not to wear quite so many hats on my next short film. I lost some of my co-producers just before production, which meant I ended up juggling a lot, but on the bright side, it pushed me to reach out for support and led me to meet some incredible new collaborators.

NFS: Is there a moment or shot you're most proud of? Why?

MB: I have so many favorite moments that I’m proud of, thanks to an incredible crew, but two stand out in particular.

The first is the very last wide shot of Cleo breaking the glass to get into the cabin while Tobias sits unaware in the sauna. This was one of the most anticipated shots, and the setups involved nearly our entire small crew—cueing actions from inside the sauna, the car, and the cabin. It was complicated, and we were running out of light, but it turned out exactly as I had hoped, and I love every little detail, right up to Tobias being locked out. Again.

The second is what I call the “I’m gonna steal your emotions” moment in the sauna. Cleo is crying, and Tobias mirrors both her posture and emotions, beginning to cry as well, and we rack focus to him. It’s such a subtle moment, but it shows so much about his personality, and I love how the camera captures that dynamic in both beautiful and comedic ways.

NFS: What advice would you give to other directors working on contained, psychological shorts?

MB: I would say: trust your instincts about what you’re trying to say with the film. One challenge I encountered while working on this psychological story was that the behaviors or mental states you’re exploring might not be immediately understood by others.

It helps to have a clear grasp of the psychological dynamics you want to portray and to communicate them clearly to your cast, crew, and potential producers/ financiers. Sometimes adding extra action lines or subtle cues in the script can clarify reactions and behaviors for anyone who might not immediately grasp them.

NFS: Is there anything you'd like to add?

MB: I would just say that if you see the film and relate to it on any level, please feel free to reach out to me. Emotional abuse is very isolating and often dismissed, but I’ve already received so many responses from people who found it relatable or helpful. These experiences are far more common than we often realize, and knowing that you’re not alone and that there’s a whole community that understands can be incredibly important!