It tells the story of a 17-year-old girl who gets bitten by a werewolf and slowly transforms into it as her police officer mother is unaware of her daughter's condition.
Meanwhile, in the present day Norwegian town of Nybo, 17 year old Thale Berg (Elli Rhiannon Müller Osborne) has recently moved into her new home with her family after her mother Liv (Liv Mjönes) transferred from her former job as a police officer in Oslo, to the local Nybo police force following the death of Thale's father.
While watching a horror movie with her, Thale receives a text from her high school friend Jonas Larson (Sjur Vatne Brean), inviting her for a party in the woods near the bay with the other Nybo youth.
Things don't go well at the party and Thale decides to leave early when she spots Jonas talking with Elin Gran (Silje Øksland Krohne), the local Mayor's daughter, in the woods by the bay.
The following day all people who attended the party, including Jonas and Thale as key eyewitnesses, are questioned by the police .
But before he can arrive, a mysterious one-armed man named Lars Brodin (Ståle Bjørnhaug) visits the police station and claims to Liv that the beast is a werewolf which he had been tracking his entire life throughout Scandinavia.
After the arrival of the vet and his conclusion that the murderous beast could indeed be an unusually large wolf based on the injuries of the victim and claw found on the scene, the victim's mother and Mayor of Nybo Tove Gran (Anna Drowak) vows vengeance against the beast and sends out a hunting party to kill it.
While the hunting party under the command of Liv and Eilert search the woods with the help of a tracking dog, Thale begins to have strange dreams and visions as her senses also seem to sharpen.
It is then revealed that the only fatal injury the wolf sustained, came from the silver bullet she had fired, leading Liv to believe they had indeed encountered a werewolf.
Believing the nightmare to be over, Mayor Tove gives a media statement alongside Liv, ensuring the city's safety with the demise of the beast.
After the discovery of Jonas' remains, the coroner concludes that the injuries he sustained are similar to those of Elin albeit by a smaller animal.
Lars then visits the hospital and discovers Eilert is infected by the beast, so he shuts down his life support system before leaving.
At the same time, William arrives at the scene, informing Liv that after testing the wolf body, he had found that it contained human DNA in its system, confirming they were dealing with an actual werewolf.
Arthur however is bleeding heavily from a wound he sustained and passes out behind the wheel, causing them to crash on a bridge near a crowded pub.
Seeing William is unable to fulfill the request, Jenny takes the dart and stabs it into her sister's side, putting an end to the attack.