We find Petra immersed in a new domestic balance and grappling with a new, extremely complicated case: a murder and theft of a relic inside a convent. In an attempt to unravel the mystery, Petra and Antonio must immerse themselves in the world of art theft and the highly secretive community of nuns, thus coming into contact with a concept of community that will touch Petra more deeply than she imagined.

When a prominent businessman is murdered while in the company of a young prostitute, Petra and Antonio are forced to undertake a dangerous professional journey to track down the killer. In a city unfamiliar to them, they will find unexpected help from a man who once played a pivotal role in Petra's life.