In a desolate, post-apocalyptic future, a scavenger named Mo discovers the head of a robotic warrior in a scrapyard. He brings it back to his girlfriend Jill, an artist who decides to use the robotic head in her latest sculpture. Unbeknownst to them, the robotic head belongs to a self-repairing military droid called the M.A.R.K. 13, designed for maximum lethality. Jill integrates the head into her art, but as it reactivates, it begins to reassemble itself using spare parts found around her apartment. Meanwhile, the authorities and Mo's contacts discover the droid's dangerous nature, heightening the tension.

As nighttime falls, the M.A.R.K. 13 fully reawakens and poses an imminent threat to Jill's life. The deadly machine's objective is clear, and it starts its murderous rampage within the confines of Jill's apartment. Mo, along with other characters, becomes aware of the escalating danger and races against time to warn Jill. The tension mounts, and the once seemingly indestructible machine reveals its full destructive potential. The situation turns into a harrowing fight for survival, plunging everyone into a desperate battle against an implacable enemy.