When Commissario Brunetti receives a visit from one of his wife's students with a strange and vague interest in investigating the possibility of a pardon for a crime committed by her grandfather many years ago, he thinks little of it, despite being intrigued by the girl's intelligence and moral conscience. But when the girl is found stabbed to death, Claudia Leonardo is no longer Paola's student, but instead becomes Brunetti's case.

Claudia seems to have no discernible living family, but lived with an elderly Austrian woman. When she in turn is found dead, the case begins to unlock long buried secrets of collaboration during the war, secrets few in Italy are happy to explore . . .