A young black girl is killed during what appears to be a voodoo ritual. Coliandro is assigned to care for the victim's sister, who has arrived in Bologna from Africa.

Coliandro is caught up in a bank robbery in downtown Bologna. The three young and inexperienced robbers are quickly subdued by three hostages, who, in turn, take the others hostage.

Officer Gargiulo shows up at Coliandro's house in the middle of the night, drunk and with a bloody knife in his hand: the inspector tries to reconstruct what happened, but it doesn't seem easy.

The husband of a former professor from Coliandro is murdered inside the University of Bologna. The woman is accused of the murder because of her husband's constant escapades: could this really be true?