Mimmo must investigate the deaths of Furino Villa and Carmelo Ricci, whose bodies were found lifeless inside a silo where they had inhaled carbon monoxide. Domenico will discover that the tragic outcome has roots in the past.

Mimmo investigates the case of Serena, who was involved in a car accident while returning home from a night shift at a private clinic where she worked as a nurse. But there were no skid marks on the road, and she hadn't consumed alcohol or drugs. Dodaro then decides to investigate the workplace.

Renato, a worker at the Carrara marble quarry, was found lifeless on the ground. According to the quarryman's foreman, a block crumbled and Renato fell, but Domenico noticed one detail: the victim's hair was wet, as if the body had been moved after the tragedy.

Nino Pastrengo, owner of a carnival float company, is found dead in his hangar inside the Viareggio Carnival complex. Initially, it's thought to be an unfortunate accident, then a murder orchestrated by a rival company. But was that really the case?

Habib Moradi's body is found critically ill outside the emergency room. Raffaella believes it was a beating, but Dodaro isn't convinced and fears the accident was caused by a tragic fall from scaffolding. The incident sheds light on a much more complex issue.

Inspector Dodaro is dealing with the case of Karina, a 19-year-old worker dragged into a warping machine. Initially, it's suspected that the cause of her "accidental death" was a distraction from the girl, who was tired from dance practice, but Mimmo discovers a different truth.