Cody, Cory Knauf, Q, and Elroy are second-generation bikers and drug dealers who plan to visit Cody's family at a remote cabin to celebrate his mother's birthday. Shade, Taylor Cole — Q's girlfriend and Cody's cousin — joins them for the trip. Upon arrival, they run into Cody's ex-girlfriend, Michelle, Tiffany Shepis, and her younger sister, Megan, [Christina Prousalis](/actor/christina-prousalis, who still harbors a crush on Cody.
After the party winds down, Michelle and her husband depart, leaving Megan behind with the group. As night settles, Megan glimpses figures outside the cabin and hopes for a ride, but no one responds. She returns to find her sister bloodied and near death, while Michelle pleads for help and then collapses into unconsciousness before any answers can be drawn. Simultaneously, the power fails — cars stall and cell phones lose signal — plunging the occupants into a growing sense of isolation.
In the tension that follows, Elroy assaults Michelle, only for her to unexpectedly awaken and turn the aggressor’s actions back on him. She bites him hard, tearing flesh from his neck, and Elroy screams as the attack escalates. The others intervene, restrain Michelle with tape, and try to decide what to do next.
Cody and Megan decide to seek outside aid, while Shade attempts to talk with Michelle, whom she believes may be possessed. The confrontation intensifies when Michelle lunges at Shade, forcing Shade to flee, and Q fires a rifle through the door in an attempt to create a barrier. Michelle seizes the moment, clinging to the ceiling and dropping onto Q as he steps inside, wounding him severely.
Meanwhile, Cody and Megan uncover a chilling clue: their nearest neighbor lies dead, and his wall is peppered with missing-person notes dating back to the 1950s. They hurry back to the cabin and learn the aftermath of the earlier assault — Michelle has vanished, and Q, now wounded, wants to abandon the search. Megan balks at the idea of giving up on her sister, and Cody argues that they must stay to help Elroy and find Michelle.
A heated argument between Q and Cody ends with Q walking away alone, leaving Shade behind when he refuses to be persuaded to take her along. As he trudges down the road, he encounters Michelle's husband — long believed dead but now alive again — who speaks of hearing strange, beautiful music. In the cabin, Elroy also notes hearing music, and both men are soon overcome as a blinding light erupts around them.
Vernon, Jazz, and Murderball — a trio of sadistic greasers — arrive at the cabin, seize the group, and torture them for information about Michelle. Vernon toys with Cody, hinting that Michelle is central to a chilling plan that could end humanity. The intruders temporarily leave to fetch Q's bound body, and Vernon then stabs him repeatedly with a switchblade. Shade protests, and Vernon orders Jazz to kill her. Cody and Q fight back, seize Vernon, and fire Q’s rifle, but the weapon proves ineffective. Murderball then executes Q, and Vernon reveals that he knew where Michelle was the entire time, simply relishing the torment.
Vernon claims to have inhabited a human body for sixty years and to hail from a void beyond time and space that inspired human myths about heaven and hell. After completing a ritual involving Michelle, Vernon releases Cody and Megan, expressing a strange affection for them and pity for their fate. The two fugitives escape toward a nearby town, but outside, they witness the world collapsing: people drop dead, and the sky grows ominously dark as if the end has arrived.
