11 year-old Vivi and 12-year-old Sebastian live halfway across the world from each other, but when a terrible shooting leads to the loss of people close to each of them, they end up meeting in the Rocky Mountains. Bonding through their shared grief, they quickly become friends, and decide to search together for an elusive rainbow pool as a way of saying goodbye to the ones they lost. But they soon find themselves lost on top of a super volcano, dodging bubbling mud spots, steaming hot springs, and rainbow filled calderas. As rain threatens, they're forced to construct a makeshift camp and encounter moose, wolves and a grizzly bear. But when they run out of food, their adventure becomes a race for survival as they try and find their way out of the wilderness.