Tui, a 12 year old girl, walks into a remote mountain lake on New Zealand's South Island as if to drown herself. She's pregnant and she's the daughter of Matt, a tough guy who leads what's probably a criminal gang. A police detective, Robin Griffin, who has her own history with the lake, investigates Tui's plight. We also meet a collective who are establishing a make-shift lakeside retreat for damaged women over Matt's objections and claims they are trespassing.
Tui has disappeared. Matt Mitchem, Tui's father, is unconcerned, claiming she's in hiding and capable of caring for herself. Robin wants a DNA sample from every man in town to determine who has gotten Tui pregnant. Robin also suspects a kidnapping, and she has a suspect whom she visits one evening. Robin's boss, the police inspector, seems to have a partnership with Matt. Meanwhile, the body of a man no one likes has drowned in the lake, and the lakeside collective includes women with odd proclivities.
Tui remains missing. Robin's investigation takes her first to Paradise, the women's retreat beside the lake. Her interview of GJ yields a prophecy but little information. Robin gets a search warrant for Matt's, but manages to miss a key element. Then it's back to Wolfgang's, where there's at least one dead body. She also continues to coax Johnno into a relationship. Matt takes flowers to Paradise looking for Bunny, who brushes him off, so he invites the willing Anita to join him for an Ecstasy-laced encounter that ends with his introducing her to his mother.
Robin accepts a dinner invitation from Al, learns that everyone on the force knows about her own rape when a teenager, drinks too much, and stays the night. By the next night, she's a pub chatting with one of her assailants, who may not recognize her. Her response changes her status on the force, and sends her again to Johnno. Matt mistreats Anita and goes back to Paradise to menace the women. Evidence proves that Wolfgang didn't kidnap Tui, who remains missing as the weather chills.
Al brings Robin back on the force and makes a proposal to her. Nearing death, her mother asks Robin for a promise. These emotional jolts come on top of Robin's revisiting, in conversations with Johnno, her rape at 15, and watching Al physically and emotionally mistreat a boy who's Tui's friend. Robin's mother visits GJ. Johnno calls on one of Robin's rapists. Matt returns to his mother's grave after a family argument.
Tui, Jamie, and their friends visit Paradise and have a sleepover. GJ and the other women give advice and comfort to Tui. Robin talks to women who work for Matt, hoping they'll provide evidence and testimony against him. She also questions Jamie's mother. Matt's posse confronts Tui's friends, then Matt's men find Jamie and Tui's hiding place. Robin and Johnno are back together. Al tells her that Matt wants to talk to her - to provide her with important evidence. Is he about to confess?
Robin calls on Matt who gives her information that prompts a crisis, a visit to Paradise to consult GJ, a night of heavy drinking, and Al's taking her off the case. Matt redoubles his efforts to find Tui; Johnno and Robin are close behind. A few days later is Tui's due date. A helicopter searches the woods by the lake, GJ departs Paradise, DNA test results are in, there's gun violence, and Robin follows a hunch.