In 1981, Abigail Ortiz, a young nurse, decides to move to Bayamón, Puerto Rico and transfer to the mental health clinic, "MEPSI Center" where she begins to work the night shift. It is here that she meets Luis, a charismatic guard who works at the clinic and accompanies her on her shift. While doing her job she has an incident with one of the patients which leaves her unconscious. When you wake up nothing is the same again.