When a team of researchers from Canada's Arctic Institute travel to York Factory to disinter a grave, they unwittingly stumble upon more than they bargained for buried in the permafrost. Their research is focused on the old Hudson Bay Company fort cemetery, where they are attempting to find a definitive cause of the famed "York Factory Complaint" of 1833 - 1836. But alongside the now-opened grave of Joseph Charles, a "company man" who had succumbed to the "complaint" in 1836, they find a Hudson's Bay point blanket, an artifact of particular significance to the archeologist of the team, Rachel Thompson, and an indication that Chipewyan people were likely buried there as well. Upon their return from York Factory, Thompson, another member of her team, and the bush pilot who ferried them to their research site, fall gravely ill. When infectious disease interns have the good fortune to be on hand in the remote north as part of a study, they examine the ailing pilot and are horrified to confirm that he suffers from smallpox, a disease thought eradicated worldwide in 1977. A simultaneous smallpox outbreak occurs in Russia, and suddenly the world must ask the question: how could a disease surviving only within the vault-like security of the world's two level four containment labs have been unleashed to ravage millions? Could the melting permafrost be releasing this deadly contagion? Deadly Thaw is a richly imagined story that could be ripped from news headlines emerging from a planet struggling with the impacts of global climate change. Meticulously researched, steeped in history, and offering a touching lament for the fate of many First Nations people killed by smallpox infections carried from the "old world", the story will have readers racing to reach its end and sleepless at imagining potential terrors that might await them.