Stewart Kane, an Irishman living in the Australian town of Jindabyne, is on a fishing trip in isolated hill country with three other men when they discover the body of a murdered girl in the river. Rather than return to the town immediately, they continue fishing and report their gruesome find days later. Stewart's wife Claire is the last to find out. Deeply disturbed by her husband's action, her faith in her relationship with Stewart is shaken to the core. She wants to understand and tries to make things right. In her determination to help the victim's family Claire sets herself not only against her own family and friends but also those of the dead girl. Her marriage is taken to the brink and her peaceful life with Stewart and their young son hangs in the balance.