Teenage twins battle dark forces hidden beneath Auckland's volcanoes.

Growing up on the family sheep farm was idyllic for smart, sensitive Harry Olfield, except for some knavish mischief from cocky brother Angus, until their dad has a fatal accident. Fifteen years later, Harry has finished sheep-phobia therapy and his ICT schooling and returns. Angus buys him out, all ready to present the genetically engineered Oldfield sheep he bred with a ruthless team. When environmentalist Grant steals a discarded embryo, which has sharp teeth, he gets bitten by it, and thus the first the be infected with predatory hunger and a mechanism that turns any mammal into a werewolf version. Running for the farm men, Grant's mate, student Experience, gets teamed up with Harry and his boorish but gentle pastoral youth friend Tucker. They must survive both the bloodthirsty sheep and their creators, who didn't realize this yet but dispose of an antidote.