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.

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.