In the hidden research facility 731, scientist Lee Shepard and his team guard a mysterious, ancient fire believed to be vital to humanity's survival. Over time, they feed the fire with increasingly drastic offerings, driven by the fear that if it ever goes out, the human race might perish. The fire grows stronger with each sacrifice, consuming resources, life, and even the remains of the dead. While his colleagues see the fire as essential, Lee begins to question its true nature. What if their understanding is wrong? What if the fire represents something far more destructive? Consumed by doubt, Lee quietly embarks on a secret experiment determined to find out what will happen if the fire is extinguished.