Fabián, a young man who just lost his parents, moves to the mansion where his aunt Lili and his cousin Isabel live. As days go by, Fabián will notice the strange habits of his relatives seem to suggest they are something more than human.

A man named Maupassant arrives at the hospital after cutting off his own hand, convinced that his limb wants to kill him. Obsessed, a nurse named Rosario will begin to wonder if what the patient says is true.