A tense start opens with a young woman waking up nude on the floor of a seemingly abandoned building, utterly petrified as guttural noises echo nearby. She bolts to escape, but a security guard storms in, calls out for trespassers, and when the same ominous voices rise, he fires in a panic, fatally striking the terrified woman as she collapses to the floor.
Outside, a group of friends pulls up and decides to break in, hoping to use the space for an illegal rave. They expect their friends Ghost and Brandi to already be inside, and their excitement quickly shifts to practical scavenging as they locate an old camera. The footage reveals that the young woman they just saw was Brandi, and the group assumes their friends are already busy inside, so they waste no time in setting up their own gear.
The crew splits to tackle the task at hand. Charlie, along with Kim and Scotty, takes charge of lighting and sound, while Lolli wanders deeper into the building. It isn’t long before she comes across Wade and Kenny skulking around, exchanging tense glances and sparking unease. When Charlie, the apparent leader, declares they have only an hour before the party starts, the mood hardens and a sense of danger creeps in.
A chilling moment follows as Kim climbs a tall ladder to adjust the lighting and spots a ghastly face in the darkness. The sight alarms everyone, but she dismisses it as a trick of the lighting and keeps quiet about what she saw.
Tension between Jade and Miko erupts: Jade admits she has feelings for Wade, while Miko calls him a slimeball. After Miko leaves, Jade’s mood sours when she discovers Wade’s bonding with Lolli. Jade disappears in a huff, and Lolli, in turn, is attacked by a hulking, grotesque welder-type figure who tears into her with savage force, leaving a trail of horror in his wake.
Jade returns to the group with a newfound resolve, as Charlie asks after Lolli. Kim volunteers to search for her missing friend but is snatched by two feral women who drag her away to the killer welder, who finishes off his gruesome work by disabling her with brutal efficiency.
Amid the chaos, Jade tries to bypass the mounting danger by tainting a beer to give to Wade, but Kenny grabs one too. Wade’s rudeness to Jade escalates, and Kenny defends her with a punch, knocking the beer to the floor. The two share a smoke and a moment of fragile connection, only to be suddenly assaulted by the feral women who decapitate Kenny and relentlessly pursue Jade, who fights with all her might until the monstrous welder chokes her and crushes her head with his hammer.
Meanwhile, Scotty and Miko are getting drunk, but fate catches up when Miko drinks the poisoned beer. Scotty tries to help her as they stumble into the welder’s path; the killer wastes no time, crushing Miko with the hammer and knocking Scotty unconscious.
The party finally begins in earnest, but Charlie and Enyx move to locate their friends and their vehicles are found destroyed. A disturbing discovery—something grisly and unsettling—rocks them, and they’re soon hunted by the feral killers. Enyx is slain in a brutal encounter, while Charlie finds Wade and Scotty bound to chairs, forced to witness Scotty’s crucifixion.
Charlie fights her way free, shoots the welder, and staggers back toward the party in full swing. The revelers laugh at her pleas for help, only for the welder to appear and begin a indiscriminate killing spree. The metal shutter starts to roll, and Charlie narrowly slips under it to escape while the others scream in terror as the killer claims more victims.
After the credits roll, Wade is shown still bound and gagged in the building, begging for help as the nightmare lingers in the dark.
