The distant highlands, covered in snow and strewn with ancient bones, are an alien home for a puma from South America. But when Dusk escapes her captors, reports of killing sprees of sheep and shepherds are not long to follow.

The highlands are no less alien to twins Iris and Floyd, whose family history renders them outcasts. Out of work, money and friends, they hear of the significant bounty on Dusk’s head. They decide to join the hunt.

As they journey up into the wild, haunted country, they discover there's far more to the land and people than they imagined. Forced to make an uneasy alliance with a fellow tracker, the twins’ lifelong bond is put at risk. And as the trio close in on their prey, it becomes clear where the true danger lies.