In it Zen, an Italian police detective, is pitted against the Sicilian Mafia and at the end is the subject of a bombing attack for political reasons.

Aurelio Zen gets a posting to Sicily, where he is asked to report to Rome on the work of the Direzione Investagitiva AntiMafia (DIA).

She is also enjoying a flirtation with Corinna Nunziatella, an elaborately guarded woman magistrate who is also investigating the Mafia.

This points to irregularities in the investigation of the murder of a Mafia chieftain's son and a possible Roman "third level" aiming to destabilise the powers of the old clans.

Finally he risks being taken for cross-examination by the Don of a declining clan who suspects Zen of murdering one of his henchmen.