Commissioner Leon (Miguel Angel Landa) investigates the murder of a woman in a population near the capital. The woman was raped before death and the case is complicated when his brother becomes the prime suspect, since it is a priest (Eduardo Serrano). Because of the implications that inquiries might have, Leon is pressured to keep the event as a "crab" (Cangrejo, or a unsolvable case), but he decides to comply with the law.

Ignacio is known as El Iluminado de la Esmeralda (The Enlightened One of the Emerald) for his healing powers. Urged by the eviction of the house where he lives, he decides to charge for his services with an illusionist. What he ends up with is being mistreated and taken advantage of by others, even ending up in jail. After regaining his freedom, he goes mad.