Confined to a high-security psychiatric hospital for the criminally insane, Nica Pierce grapples with the belief that she, not the possessed doll, murdered her family. After several years of therapy, Nica begins to accept the narrative that she is culpable, with the conviction solidifying under the care of Dr. Foley, who introduces a Good Guy doll as a therapeutic tool for Nica and her fellow patients. The doll's presence induces unease among the occupants, sparking a chain of eerie occurrences within the institution's sterile halls.

Meanwhile, Andy Barclay, the doll's original owner and survivor of its initial rampage, continues to struggle with the trauma inflicted by his childhood experiences. When Andy becomes aware of the doll's intrusion into the psychiatric facility, he aims to confront his past demon and put an end to the cycle of terror. The institution becomes a battleground of manipulation and horror as the doll sets into motion a sinister plan, revealing it harbors secrets that threaten to unhinge the fragile minds of all within its reach.