From shipwrecked cats to beasts of burden to foxes brought in for sport hunting, the non-native animals that now run wild all over Australia’s vast countryside have made the land their own so effectively and with such far reaching implications they are now the biggest threat to its native wildlife, destroying its environment, scarring its landscape and costing millions. No longer serving the use they were brought in for, multiplying and thriving in a land free from predators that could counter them the feral animals of Australia have committed crimes of survival that have led to the extinction of more mammal species than anywhere else in the world, the continuing decline of a great many more, the decimation of thousands of hectares of pristine wetland and rainforest and the potential spread of noxious and fatal diseases. Who are the victims? Who are the perpetrators? Where are the battlegrounds and why are the stakes so high? In this documentary series we go where the buffalo roam, where the wild horses run free and the cats and foxes prowl. We follow the trail of decimation and destruction these and other pest animals have wrought, meet the glorious native animals they are on the brink of wiping out and explore the architecture of this vast and beautiful land that makes it so vulnerable to the pests it harbours.