Five friends gather at a remote cabin in the woods, where they find a mysterious book, the Naturon Demonto—an ancient Sumerian text bound in human flesh and inked in blood. Despite decipherable warnings scrawled on its pages, one of them, Eric, utters aloud a cursed incantation. This reckless act awakens an evil force lurking in the woods. Unleashed, the malevolent presence seeks to possess and destroy them, starting with Mia, who is already vulnerable and struggling with her recent attempt at sobriety.

The group initially dismisses Mia's frantic claims of encountering a malevolent being, rationalizing her panic as withdrawal symptoms. However, it becomes clear that the menacing force has taken hold of Mia, whose behavior becomes increasingly erratic and violent. As the entity's power intensifies, it begins a brutal assault on the cabin's inhabitants, forcing the friends into a desperate fight for survival. They must confront the malevolent force, unraveling its intent to destroy them all, whilst dark secrets and forgotten memories surface, severely testing their resilience and friendship.