Viking Wolf

Thale becomes infected during the party attack when she tries to help Elin Gran. The werewolf that attacks Elin also wounds Thale, likely transferring the curse through its claw or blood. This infection lies dormant until the first full moon triggers her transformation.

Earlier in the film, Thale begins experiencing strange dreams and heightened senses, hinting at the curse awakening inside her.

Silver has long been associated with supernatural creatures in folklore as a purification metal. When Liv shoots the first werewolf with the silver bullet Lars Brodin gave her, the bullet proves fatal while regular bullets have no effect. This silver weakness becomes the only reliable method to kill the werewolf threat throughout the film.

Lars deliberately leaves the silver bullet for Liv, suggesting he knows from experience that standard weapons won't work.

Jonas meets Thale at a viewpoint for a romantic encounter, but a full moon rises and triggers Thale's transformation. She loses control of her human self and attacks Jonas, killing him. The coroner later confirms his injuries match those of Elin but from a smaller predator, confirming Thale was the werewolf all along.

Thale has been experiencing intensified visions and odd cravings since the party attack, building toward this tragic moment.

Lars explains that once someone is transformed into a werewolf, their humanity is completely lost and the only way to end the curse is to kill the entire bloodline. After Eilert is wounded in the mine attack and contracts the werewolf infection, Lars returns to the hospital and shuts off Eilert's life support to prevent the curse from spreading further through another carrier.

Earlier, Lars warns that the werewolf curse spreads through those who survive an attack.

The film opens in 1050 during a Viking raid on a Normandy monastery. The Vikings discover a wolf cub hidden behind a locked door and bring it back to Norway as compensation for lost treasure. By the time the ship reaches the Norwegian coast, all the Vikings have been killed by the cub, which then escapes into the wilderness. This ancient wolf is the ancestor of the modern werewolf terrorizing Nybo.

The opening scene shows the wolf cub killing its captors, establishing the creature's deadly nature from the start.

The curse spreads through werewolf attacks. When Elin Gran is attacked and killed, Thale is also wounded during her rescue attempt, becoming infected. Later, Eilert Sundas is wounded during the mine attack and contracts the curse as well. Anyone attacked by a werewolf who survives becomes a new carrier of the curse.

Lars tells Liv early on that the creature is a werewolf he has tracked across Scandinavia, implying it has killed before.

Once transformed under the full moon, Thale loses her humanity completely. She no longer recognizes family members and acts purely on predatory instinct. This is why she chases Arthur and Jenny through the city and corners her younger sister Jenny, despite their close bond. The curse erases her identity and connections to loved ones.

Lars explicitly states that once transformed, a werewolf's humanity is gone and cannot be restored.

After the hospital confrontation, Thale escapes and boards a night bus heading to Oslo. Another full moon rises as the bus enters a tunnel, triggering her transformation. The fully transformed Thale attacks the passengers, causing the bus to crash. Survivors report a wolf attack at the scene, and later examination confirms the wolf contained human DNA.

Thale's earlier full moon transformation at the viewpoint shows her uncontrollable nature.

During the final confrontation at the store under construction, Thale is attacking her mother Liv. Jenny, who is deaf, sees the danger and acts decisively to save her mother by stabbing the tranquilizer injector into Thale's side. This stops Thale's attack and allows the others to contain her.

Jenny has been shown throughout the film as the family member Thale is closest to and most protective of.

Thale is subdued with a tranquilizer and kept under watch at the veterinary clinic. Liv loads the silver bullet and contemplates whether to kill her daughter to end the nightmare. The film ends ambiguously with Liv placing the silver bullet beside a photo of Thale on her nightstand, leaving whether she chooses euthanasia or exile to spare the town from further bloodshed unresolved.

The entire film builds toward this impossible moral choice between saving Thale and protecting the town.

Lars Brodin is a mysterious one-armed man who claims to have tracked the werewolf across Scandinavia. He appears to be an experienced hunter of supernatural creatures, possessing knowledge of werewolf weaknesses and the silver bullet. His personal motivation is unclear, but he seems driven to contain the curse before it spreads further.

Lars dismisses the police investigation as useless and provides the only effective weapon against the creature.

After the bus crash, veterinarian William Nordvaag examines the wolf body found at the scene. He discovers that the wolf contains human DNA, which proves definitively that the creature is a werewolf. Combined with Jonas' death matching Elin's injuries, this confirms that Thale herself is the transformed werewolf.

The film repeatedly shows Thale experiencing visions and cravings that align with werewolf transformation.