A crime drama about the disappearance of a pregnant 12-year-old New Zealander begins with a detective, who's visiting her ailing mother, being brought into the case and encountering roadblocks in the form of the girl's tight-knit and tight-lipped family, a felonious crew who live in a mountain compound.

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's investigation takes her to the place where Tui was last seen, the women's camp at Paradise, and her interrogation of GJ goes nowhere as the camp guru instead grills Robin. Later, Robin obtains a warrant to search Matt Mitcham's house, and uncovers something surprising.

After a unhappy incident, Robin's job is threatened but she won't give up. She finds a boy who might hold clues to Tui's case, but will he talk?

Regardless of past relationship problems and a secret that haunts them, Robin and Johnno begin to grow closer, despite her mother's objections. Later, Matt sends henchmen into the bush to find Tui, so Robin and Johnno follow them and uncover shocking evidence. Meanwhile, Tui's mute friend is caught stealing and is arrested and interrogated, which puts a new wrinkle in the investigation.

Robin senses a connection between Matt's illegal activities and Tui's disappearance, so she quizzes the women who work for him, but they refuse to cooperate. Later, Robin is threatened and told to end her investigation; and a group of Tui's friends gather to undertake a secret trip that could reveal the girl's whereabouts, while Matt launches his own full-scale search party that includes armed henchmen.

In the series finale, Tui's due date nears and she's still missing in the wild, while Robin goes to Matt's house, where his confession is wholly unexpected and thoroughly shocking, and seriously impacts her relationship with Johnny. Finally, a frustrated Matt takes matters into his own hands, leaving Robin in a frantic race to find Tui before he does.