In December 2004, a writer named Russell Core, who specializes in wolf behavior, receives a call from Medora Slone to travel to the remote village of Keelut, Alaska. Medora seeks Core's help to hunt down the wolves that are suspected of causing the tragic disappearances and presumed deaths of three young children, including her own 6-year-old son, Bailey.
Upon arriving, Core stays at the Slone residence, where he engages in conversations with Medora about the missing children. She reveals the existence of hot springs just north of town, igniting Core's curiosity. One peculiar night, he is awakened by the sound of Medora whispering and bathing. Dressed in a dark wooden wolf mask, she approaches him and, after removing the mask, insists on intimacy by forcefully moving his hand to her neck.
Meanwhile, Medora's husband, Vernon Slone, serves overseas in Iraq, portrayed as a ruthless soldier adept at taking down militants. One harrowing day, he discovers an American soldier assaulting a local woman and decides to intervene violently, leading to a deadly confrontation. Although he survives a gunshot at a checkpoint, the trauma lingers.
The next morning, Core ventures into the wilderness to track the wolves. He encounters an elderly native woman named Illanaq, who warns him that he is heading in the wrong direction and cryptically mentions that Medora "knows evil." During his exploration, Core stumbles upon the hot springs Medora spoke of and witnesses a pack of wolves feeding on their offspring. Tormented by the sight, he chooses not to harm them and returns to Keelut only to find Medora has vanished, leaving behind an unlocked cellar door.
Descending into the cellar, Core discovers Bailey's frozen body, leading him to call for immediate assistance. The local police investigate the gruesome scene, while native villagers claim Medora is under the influence of a malevolent wolf-demon known as a tournaq.
In the meantime, Vernon reconnects with his old friend Cheeon, who is also grieving the loss of his child. They meet at the airport and subsequently join forces with Donald Marium, the police chief, as they gather at the morgue. Unbeknownst to them, Vernon unleashes chaos by shooting the officers after being provoked into a corner, and he, along with Cheeon, ritualistically buries Bailey's body, marking the grave with their blood.
As Core recalls Illanaq's ominous warning about Medora, the police mobilize to apprehend Cheeon, who violently retaliates against them with an M60 machine gun, resulting in significant casualties. In a parallel storyline, Vernon, driven by past demons, meets an old hunter named John, who attempts to help him confront his psychopathy rooted in wolf lore. After a brutal confrontation, Vernon dons a wolf mask and kills John, solidifying his descent into darkness.
Core and Marium piece together that Medora may have sacrificed Bailey to shield him from impending darkness. They contemplate her whereabouts—potentially back at the hot springs. Meanwhile, Vernon, consumed by hallucinations of Medora, commits another gruesome act, killing his old friend Shan when he informs the police of Vernon's presence.
At the hot springs, an eerie confrontation unfolds where Marium is shot by Vernon, who is now completely enveloped in his wolf persona. Core, determined to save Medora, encounters her in a tense moment before Porter, in a final fit of rage, shoots him too.
As Core drifts into unconsciousness, Medora manages to dislodge the mask from Vernon, leading to a fleeting moment of connection before Core succumbs. When he awakens, he finds himself in a hospital room, his daughter Amy by his side, while Vernon is seen in the snow, digging up Bailey's grave with Medora, their grim intentions unfolding amidst the haunting backdrop of the Alaskan wilderness.
