Daniele, Sabina's brilliant computer scientist partner, is involved by Mauro in the investigation into the ecomafia: his help is needed to decrypt Liverani's CD-ROM. Giulia decides to cover for her men, unleashing the ire of prosecutor Altieri who had assigned the investigation to the Carabinieri. Davide is also hurt by Giulia's choice but she explains her doubts to him. In the meantime, Anna and Luca confront each other on a delicate family case: eleven-year-old Stella accuses her stepfather of having molested her; in reaction, the girl's father brutally attacks his wife's new partner, who in the end turns out to be innocent. Anna confides in Luca that at the same age as Stella she was raped by her stepfather. Meanwhile, Terenzi's two murderers show up at the X Tuscolano disguised as Carabinieri demanding the CD-ROM.