After the meltdown of three nuclear power plants created an energy crisis in 2018, Auxilisun built a tri-fission engine over the disaster site to create a renewable energy resource from the radiation it was cleaning, leading to the energy revolution of 2025.When communications are lost with the Gibson Desert North facility on Christmas, Auxilisun chief technical engineer Abby Dixon elects to investigate personally and get the system back online. Abby arrives at the facility to find it in an unexpected state of neglect and meets caretaker Robinson Scott, who behaves furtively and is generally uncooperative. Robinson tells Abby that chief scientific executive Dr. Darius Zek, the only other person stationed there, is away surveying a surrounding area and he doesn't know when Zek will return.While Abby inspects the facility's functions and spends more time with the odd man, she notes that Robinson's physical health is poor. Abby also discovers that the facility's power lines were intentionally severed and the red zone danger area protected by the tri-fission engine appears to be expanding.After briefly seeing someone in the desert outside through a security monitor, Abby asks Robinson what he isn't telling her about Dr. Zek. Robinson claims that before he left several days earlier, Zek seemingly went mad from sensory deprivation psychosis due to their isolation and may have been exposed to radiation in the deep burial containment chamber.Abby later picks up Zek's signal on a scanner. Abby ventures out into the desert, finds Zek lying unconscious, and physically drags him back to the facility. Robinson handcuffs Zek to his gurney claiming it is for their personal protection.An alert sounds. Abby watches as one of the two essential radiation cooling fans stops working. Abby sends a request for an emergency repair team with the suggestion that she believes someone intentionally sabotaged the engine room.Zek comes out of his coma. Zek tells Abby in confidence that Robinson is an imposter who infiltrated the facility as a terrorist. He stresses that Abby shouldn't let on that she knows the truth until they know what Robinson wants.Abby finds home movies of Robinson with his family from a nearby town that was poisoned by radiation. After going back to the desert to send a distress signal, Abby returns to the infirmary and releases Zek.Robinson confronts Zek and Abby, demanding that Zek tell Abby the truth about the Gibson Desert North facility. Zek claims to have no idea what Robinson is talking about. Zek attacks Robinson with a laser cutter in order to escape and locks Abby and Robinson inside the infirmary.Robinson tells Abby that Zek is a lunatic who turned the facility into a bomb. Abby rewires the door so they can escape the room. While Robinson goes looking for Zek, Abby finds the real Robinson's body along with the imposter's family photos.Robinson confronts Zek and the two men fight. Abby intervenes and fights with Robinson. Abby realizes that Robinson has radiation sickness from prolonged exposure. Robinson cuts off Abby's finger and uses it to access the deep burial chamber.Abby condemns Zek when she concludes that he knew the facility was decaying and the red zone was expanding. Zek tells her that Auxilisun already knows about the contamination, but they deliberately kept it quiet because the energy benefits were deemed more important than the residents of surrounding towns. Abby leaves Zek to fend for himself.Abby confronts Robinson in the containment chamber. Robinson mourns his dead wife and son before taking a lit flare and diving into the radiation core. The facility begins crumbling.Abby escapes to the desert before the facility is completely destroyed, but she is killed by the resulting radiation cloud emanation. An Auxilisun recovery team later finds Abby's corpse and bags her tablet alongside other evidence kept in boxes.