At the seaside resort of Riccione in 1938 the body of a young prostitute is found on a beach, not far from Mussolini's holiday residence. The local chief of police, terrified that the news may become public, attempts to draw the matter to a swift close by charging the woman's pimp with her murder, and earns praise from Il Duce in the process. But Inspector De Luca, unconvinced that the case has been solved, continues to secretly investigate on his own. Set against the backdrop of sophisticated hotels and exclusive beach resorts in what was once considered to be the 'summer capital' of fascism, De Luca's investigation soon starts to involve aspiring politicians, high-ranking state functionaries, seductive countesses, anti-fascist journalists and some of Mussolini's own bodyguards.

In April 1945, having inadvertently been credited with 'saving Il Duce's life', De Luca becomes a reluctant hero and is promoted to a high-profile job in Bologna. He heads a murder investigation which will lead him to probe the private lives of the rich and powerful during the frantic final days of the fascist regime. The powers-that-be grant him carte blanche, just as long as he arrests the 'right' suspect.

June 1945, and WWII has been over for a few months. As a police officer under the former fascist regime, De Luca now reluctantly finds himself on the wrong side of the law. After being involved in a violent incident at a roadblock he goes on the run, but when he tries to re-enter civilian society under a false identity he is recognised by an officer of the partisan police and roped into investigating the murder of a local peasant. Fearing that his cover may be blown at any moment, De Luca pursues the case with the junior officer and investigates the local community, the disappearance of an aristocrat and the possible involvement of British Army officers stationed in the area.

April 1948, and demoted to the role of deputy inspector and assigned to the vice squad, De Luca returns to Bologna. As the first elections of the newly-formed Italian Republic are about to take place, a man is found hanged in a brothel. Although the authorities are quick to pronounce the incident death by suicide, De Luca suspects foul play. His dogged determination provokes a stand-off with his superiors, and the investigation takes a further turn for the personal when the inspector runs into the madam of a brothel located in Via Delle Oche.