As Tui's disappearance remains unsolved, fear for her survival increases, while her father solicits help, Robin has a run-in with the girl's half-brother and a perverted local.

Robin makes a breakthrough in her investigation, but Al warns that her own dark past is colouring her judgement.

A violent indiscretion sees Robin thrown off the case but she cannot let go. Her passionate affair with Johnno, Tui's half-brother, intensifies and complicates.

Robin is back on the case, whilst Matt gathers troops to hunt his daughter down. Tui's friends trek deep into the mountains to celebrate her birthday, with tragic consequences.

With fresh intelligence on where Tui’s hiding, Matt launches a full-scale search party. Before Robin can intervene, tragedy strikes.

Tui is about to give birth. Matt reveals a secret that almost destroys Robin. The investigation reaches its shocking conclusion.