Arsenic Trioxide is a highly toxic contaminant that is currently buried underground on the Giant Mine Site. It is an invisible presence within the lives of the aboriginal communities of Dettah and N'dilo and the Northwest Territories capital city, Yellowknife. Eighty metres underground within Yellowknife city limits, on the traditional territory of the Yellowknives First Nations beside the 9th largest Lake in the world, sits 237,000 tons of arsenic trioxide. The Arsenic sits in the old mine workings of an aging, crumbling mine site within a porous rock that is permeable to water. The permafrost that once encased the poison has now melted. Once dissolved in water, it is colourless, tasteless and odourless, and an aspirin sized dose could kill you. Above ground, the city of Yellowknife and the aboriginal communities depend on the environmental monitoring by the federal government to assure that their water and the places where they live, are safe. They depend on a remediation plan that will, at best, refreeze the arsenic trioxide underground until a permanent solution can eventually, if ever, be found. And finally, they are left footing the bill of a financial cost that far exceeded any benefits that were seen by either the government of Canada or the communities around Yellowknife, and are left with the cultural and environmental harm that can never be undone.

Shadow of a Giant tells the story of Giant Mine through the people who live on top of it and call it their home: From the remediation (clean up) team, that works to stabilize the arsenic before it further contaminates the surrounding environment; to the people who live and work in Yellowknife; to those who worked at the mine; from the proponents of the extraction industry in the north; to the Yellowknives Dene First Nations that lives hundreds of metres from the contaminated site. Their voices are the ones who tell the story of Giant from the perspective of the local community.