Forty-six years ago, a calamitous event occurred, locking the world in an endless winter. Now, the city of Coldhaven stands isolated, struggling to survive the unending cold with what meager resources they can produce and salvage. Responsible for maintaining the city's steam systems, Joe Kennedy spends his days repairing the complex network of pipes that provide the life-giving heat to the citizens of Coldhaven. When the medicine that keeps his young daughter's condition in check runs low, things become desperate for Joe and his family. Denied the critical resource by the city's harsh decrees, he is forced to seek salvation in the only place left to him: the frozen expanse. With few options remaining, he secures a spot on one of the balloon teams-a precarious venture that may provide access to lost caches of resources. Risking everything he has ever known, his journey takes him farther than he ever thought possible, out into the distant snow and beyond.