Shelly is house-sitting for the first time at the Ferguson place. With the family gone for the weekend, she is left alone in the secluded house nestled within the hills. Or so she thinks. She quickly learns that there are other inhabitants living under the house. Inhuman underground residents, hell-bent on violating every inch of her flesh. Both external and internal. A small door in the kitchen pantry turns out to be a gateway revealing a labyrinth of perversions and depraved decadence beyond her imagination. Shelly is unwillingly guided through the threshold, down into the caverns below the Ferguson house. What she encounters down there, will test every molecule of her physical, emotional, mental, and sexual ability.