THE FILM
The inspiration for the film came when director J. Zachary Thurman first learned of Louis Slotin’s extraordinary bravery and sacrifice. The screenplay research took four months, including two trips to Los Alamos, meeting individuals who grew up there, and studying declassified documents. Thurman gained exclusive access to the Slotin Building, the site of the incident, where he had a deeply moving experience that solidified his commitment to telling Louis' story.
“Standing there, on the ground where Louis made his heroic stand to save his colleagues, was a profoundly moving experience. It was hauntingly beautiful, and in that moment, I knew deep within my soul that I had an obligation—to honor Louis’ story, to share his bravery and selflessness with the world, and to ensure that his legacy would live on.” - J. Zachary Thurman
With the story clear, Thurman wrote the screenplay in just three days. It was soon awarded the prestigious Sloan Foundation Grant, which recognizes filmmakers blending science with narrative to raise public awareness. Pre-production began with SPFX Makeup Lead Patrick Bradberry recreating Louis’ radiated hands/arms, and Nascent Perspective Studios making an exact replica of the "Demon Core" prop. The team also partnered with ARRI Rental, which donated camera equipment, and Nanlux, which provided the latest lighting technology to achieve the film’s distinct look.
Principal production spanned three blocks: three days in Burbank, CA, filming the Slotin Building replica; at the Historic Wendover Airfield in Utah, home of the Enola Gay; and finally in New Mexico at Los Alamos National Labs and Ghost Ranch, where they shot on the actual Oppenheimer set.Post-production took a month for editing, followed by two months for VFX, sound design, and music recording. Walter Volpatto, known for his work on Interstellar and The Last Jedi, served as the senior colorist, giving the film a 1946-era look and feel.
This film is a testament to what can be achieved with determination, passion, and a DIY spirit. Our goal is clear: to make Louis Slotin and Harry Daghlian household names. These two men, whose sacrifices helped shape modern science, have been largely forgotten by history. Through this film, we aim to correct that, highlighting their contributions and educating audiences. Ultimately, we want The Demon Core to take viewers on an emotional journey, evoking the weight of Louis’ sacrifice and the humanity behind his story.
THE HISTORY
On the afternoon of May 21, 1946, at a secret laboratory just outside of Los Alamos, New Mexico, a demonstration took place that would end in tragedy. Louis Slotin, a Canadian physicist and expert on handling plutonium, was showing colleagues how to bring the exposed core to the point of criticality, a delicate operation known as “tickling the dragon’s tail.”
The demonstration was simple: Slotin would lower a half-shell of beryllium over the core, stopping just before it seated completely. This would reflect neutrons back onto the plutonium, triggering a brief nuclear chain reaction. Slotin held the tamper in his left hand and a long screwdriver in his right, preparing to keep the components apart. As he proceeded, one of his colleagues, Raemer Schreiber, turned away, expecting the experiment to take a while. But suddenly, he heard a sound: Slotin’s screwdriver slipped, and the tamper dropped fully over the core. Schreiber turned to see a flash of blue light and felt a wave of heat.
The blue flash was a result of intense radiation, a burst of energy as the fission reactions occurred. Slotin quickly removed the tamper, but the damage was done. It was calculated that the number of fission reactions was around three quadrillion, enough to release a significant amount of radiation. Slotin and his colleagues, now realizing the severity of the situation, were taken to the Los Alamos hospital. Despite initial signs of recovery, Slotin’s health rapidly deteriorated. His white blood cell count dropped, and he began to suffer from internal radiation burns, severe pain, and mental confusion. Nine days after the accident, he died from acute radiation syndrome at the age of 35.
Slotin’s death was one of only two radiation-related fatalities at Los Alamos during its military control. Nine months before, Harry Daghlian, Jr., had suffered a similar fate after a criticality accident involving the same core. After Slotin’s accident, all further criticality experiments were halted. The urgency of wartime research had prioritized speed over safety. With the Cold War looming, a memo called for using remote controls and increasing safety precautions for future experiments.
The core that caused both Daghlian and Slotin’s deaths, initially nicknamed “Rufus,” would forever be known as the “demon core” and the tragic events involving the it served as a stark reminder of the dangers of nuclear experimentation and the human cost of scientific progress.
DIRECTOR
STATEMENT
Two years ago, if you had asked me who my hero was, I couldn’t have answered honestly—I didn’t fully understand what it meant to be a hero. Then I discovered the story of Louis Alexander Slotin, and now, without hesitation, I can say he is my hero.
From the outset of this project, my goal was clear: to honor Louis Slotin’s legacy with everything I had. Why? Because Louis gave everything to his craft and to science—and I felt compelled to do no less. The journey, however, was anything but easy. During production, I was diagnosed with a rare autoimmune disease and a large brain mass. On the day I received my diagnosis, I was filming the dream sequence. I kept this news to myself, internalizing it and using it to connect with Louis’s own emotional turmoil—the loss of his life before the incident. This personal connection stayed with me throughout filming and post-production, where I hand to undergo chemotherapy. I share this not for sympathy, but to explain how deeply I could relate to Louis’s courage in the face of an unimaginable fate, and how that fueled my own resolve to receive treatment, finish the film, and share his story.
The process was grueling, but the incredible team behind this project exceeded my expectations. Together, we were granted a once-in-a-lifetime opportunity—to travel back in time and restore a story history had forgotten. It’s my hope that The Demon Core corrects this historical oversight and ensures Louis Slotin’s name is remembered for generations to come. When people think of Los Alamos during WWII, I hope they not only remember Oppenheimer and the bomb, but also a group of “cowboy scientists”—young, fearless physicists pushing the boundaries of science for the betterment of humanity, no matter the cost.