Every Bitter Thing

The son of the Venezuelan Foreign Minister is found dead in his apartment in Bras lia, the victim of a crime of passion, or so it seems. Due to the high-profile nature of the case, Chief Inspector Mario Silva of Brazil's Federal Police is called in to investigate. As he delves deeper, he discovers that a chain of murders have occurred throughout Brazil, all with the same MO. They seem to be the work of the same killer--but the victims, of diverse ethnicities, cities of residence, economic classes, and walks of life, have nothing in common. What sinister motive connects these killings?