Boobs, Blood, and Music numbers! That's right. Skeleton Key is back for its final installment. Join Howard as he ventures through notes and nipples coming up against monsters and zombies again and again. Joined by Nicopernicus, Arbuckle, Guy, Codo, and Mandy, Howard must fix the world of its monster infestation that have escaped the town borders of Nilbog!

The final night’s work approaches for the staff of an insane asylum. A minimal crew of security and researchers remain to ensure the patients behave as expected before their transfers to a maximum security prison. Struggling with memories of abandonment, Dr. Helen Kingford finds herself on the brink of quitting her job as a psychologist. Following his forced retirement, the hospital's head of security decides on a destabilizing course of action leading to chaos and destruction within the asylum. In the confusion, all of the dangerous patients escape their padded cells. Confused, Dr. Kingford awakens finding herself tied up in the hospital morgue. Not knowing who to trust, she finds herself running from everyone in an attempt to survive.