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.

Anthology film of classics police stories written and directed by Marcos Moreno