A deadly virus spread by rainfall forces siblings Simone and Rasmus to seek refuge in an underground bunker, parting ways with their scientist father.

After six years of isolation, Simone and Rasmus encounter other survivors. To stay alive, Simone must prove herself useful to the group.

Simone and the others set out for Apollon headquarters in Sweden, but their trek through Copenhagen is fraught with peril.

Jealousy flares in Martin and Beatrice. Simone and Rasmus meet a doctor with a connection to their father. A memory haunts Jean.

Lost in the woods, the group stumbles upon a mansion. The residents invite them to stay the night, and Lea bonds with one of the women.

Rasmus and Beatrice grow closer as they spend time alone together. The others discover a new bunker -- and a disturbing secret that lies within.

A band of armed strangers tries to extract information from Patrick. Rasmus begins to unravel in the wake of a grim discovery.

The group arrives at Apollon headquarters, where Simone learns startling truths about the virus, her father and Rasmus.

On the run from Apollon soldiers, the group follows a set of coordinates to a base where rebel scientists are working on a vaccine for the virus.

Martin accompanies Simone on a journey to retrieve her father's computer. At the base, Patrick stumbles upon a hidden room filled with strange devices.

As Apollon surrounds the base, Simone scrambles to find a cure. Rasmus's secret draws Sarah to him -- but threatens to tear the group apart.

Simone, Martin and Fie pursue Rasmus and Sarah, whose bond deepens while they're on the run. Patrick makes another discovery. Jean tries to console Lea.

Plagued by frightening visions, Rasmus takes his fate into his own hands. Sarah's health worsens. Jean and Lea share a tender moment.

In the wake of their grim encounter, Martin and Patrick race back to the base. Meanwhile, a grief-stricken survivor plots revenge.

Haunted by nightmares and afraid of his newfound powers, Rasmus voluntarily confines himself at Apollon. Meanwhile, Simone ventures beyond the wall.

Simone meets a brother and sister living off the grid. Back at Apollon, Patrick and Fie weigh their options, and Rasmus makes a horrifying discovery.

Simone refuses to leave unless Daniel gives her the flower extract. Sten wants to test Fie's theory and threatens Rasmus to ensure his cooperation.

Simone's group approaches a camp of young survivors. Rasmus's thirst for power spirals out of control, and Martin leaves Apollon to search for Simone.

As Rasmus grows weaker, a worried Sarah asks Fie for help. Reunited, Martin and Simone begin the long trek back to Apollon.

A surprising revelation sparks new hope — but Simone and the others must ready themselves for a dangerous confrontation as Rasmus closes in.