Guido's undercover past threatens his job at Southwest 101 when he becomes the prime suspect in the murder of Vincent Rinaldi, a crime figure Guido was involved with while working undercover and whose $2 million he is now being accused of stealing. As his colleagues' trust in him is put to the test, Guido's sole focus is on locating a missing 18-year-old girl, leaving him at risk of sacrificing everything for a girl he has never even met.

A reporter's interest in a fatal hostel arson case in which an alleged police cover-up sent the wrong man to prison prompts Kostas to put the Eddie and Donna on the reopened case. When Guido learns the target of their investigation he is forced to confront the truth about his legendary detective father and the role he played in the conviction.

Donna and lawyer flatmate Madeleine Delaney are in ethical conflict as they fight to save a woman charged with murder for preventing rape.

Guido's Naval Captain brother, the favoured older son, returns home a hero, and tensions between the brothers surface as a female naval officer is found murdered. Cameron again finds herself working alongside Bill Martin to rein in a Chinese gang leader.

Guido and Cameron each face a personal crisis—and their friendship is tested—as Guido's father and brother come under suspicion.

Cameron feels that a girl found dead in a hotel penthouse is treated like party debris both by the elite partygoers and some investigators. Paul Bergin asks Guido's father for help to bring down a Chinese gang boss.

Guido's friends rally to his side as his father faces a terminal illness—and a murder charge.