Deep underground, below Valkyrien Square in Oslo, doomsday prepper Leif has arranged a place for doctor Ravn Eikanger to carry out research into his wife Vilma's terminal illness in secret. Above the surface Ravn keeps up the pretense of mourning his wife while below it, a severely injured robber Teo seeks refuge with Leif. Without medical attention, Teo will die and Ravn owes Leif a favor.

Ravn is clutching at straws, searching for something that can help Vilma. Against Leif's will, Ravn decides to let Vilma's research colleague Unn in on the secret. Teo, trapped underground and separated from his pregnant wife Marit, dreams of building a shelter for himself and his family and Leif is keen to help. This, however, requires resources, so Leif begins to make demands of his tenants.

The clinic is open. Leif provides the patients, while Ravn and Unn treat them the best they can. At the same time, they begin to make progress with Vilma's treatment. But Vilma's daughter Siv has begun to ask questions. Leif is under scrutiny by the police, who suspect he had a hand in the robbery and an unexpected challenge arises in his job at the City's Emergency Planning Agency.

A humiliating conversation with his brother forces Leif to reconsider his leadership style. Teo puts both himself and the clinic at risk by seeking out his wife, Marit. A patient gives Ravn an idea that could help Vilma, but before he can give Vilma a new drug, he needs a test subject - someone expendable.

A patient brings a deadly virus into the clinic. Vilma becomes infected and Ravn must make the most difficult choice of his life. While Unn works hard to gain control of the infection, Leif implements his own plan. A pandemic is after all a threat he and his like-minded comrades have been preparing to face.

Vilma has disappeared. Ravn and Leif must find her before someone else does. While they desperately hunt for her on the surface, the police officer Per breaks into Leif's tunnels and bomb shelters below ground. And in the clinic, Teo finds himself completely alone.

Ravn has a lot of explaining to do and family, friends and the media are not buying his story. Grethe and the hospital recognize in Vilma a medical phenomenon, and propose a risky solution. With Unn back at the hospital, and Teo in prison, Leif is alone in an empty clinic.

Oslo is in crisis after several days without power. Leif secretly rejoices over his actions, but still doesn't get the affirmation he's always dreamed of. Vilma is desperate to understand her own miracle, and Ravn's love for her is tested to the limit. When an emergency generator at the hospital breaks down, Ravn and Unn have only one course of action left.