Inspector Montalbano is puzzled by the kidnapping of Susanna Mistretta, a young woman whose once-wealthy family has fallen on hard times. When the kidnappers contact the family to demand a ransom, the responsibility of coming up with the money falls on an estranged relative. But something in the case just doesn't add up.

The death of local construction magnate Girolamo Cascio leads Montalbano back to the murder of Cascio's leading competitor, Giacomo Aletto, who was shot and killed two decades earlier. Rocco Pennisi, Aletto's partner, was sent to prison for the crime. But was the right man convicted?