University psychologist Estela Nogales is caught at work when the perfect murder sets off chaos on campus during final exams week. Together with her law enforcement buddy, Detective Muñoz, who is stymied by the lack of evidence and his potential witnesses scattering for the summer, Estela must use her intuition and acute powers of observation to help identify the killer. Set against the usual campus confusion, one crisis after another disrupts the investigation and Estela is pursued at every turn by the mysterious figure in the hat, even home to Arroyo Loco where a new set of crises are unleashed.