Ever wonder where American gets most of its oil? If you thought it was Saudi Arabia or Iraq, you are wrong. America's biggest oil supplier has quickly become Canada's oil sands. Located under Alberta's pristine boreal forests, the process of oil sands extraction uses up to four barrels of fresh water to produce only one barrel of crude oil. It goes without saying that water—its depletion, exploitation, privatization and contamination—has become the most important issue to face humanity in this century. At the same time, the war for oil is well underway across the globe. A struggle is increasingly being fought between water and oil, not only over them. Alberta's oil sands are at the centre of this tension. As the province rushes towards a large-scale extraction, the social, ecological and human impacts are hitting a crisis point. In only a few short years the continent will be a crisscross of pipelines, reaching from the arctic all the way to the southern US, leaving toxic water basins the size of Lake Ontario, and surface-mines as large as Florida. H2Oil follows a voyage of discovery, heartbreak and politicization in the stories of those attempting to defend water in Alberta against tar sands expansion. Unlikely alliances are built and lives are changed as they come up against the largest industrial project in human history.