Six Degrees Could Change the World structures itself around a single number: how much the planet's average temperature might rise, and what happens at each step from one degree to six. Based on Mark Lynas's research into climate projections, the film moves incrementally, showing coral bleaching and shifting agriculture at the lower end of the scale before turning to melting ice sheets, disappearing coastlines, and the kind of mass extinction scenarios scientists associate with the higher degrees. Interviews with climate researchers and simulated visualizations stand in for footage that does not exist yet, translating abstract temperature curves into flooded cities and stressed ecosystems. The degree-by-degree format is the film's organizing device throughout, treating each increment as its own chapter with its own set of consequences rather than presenting warming as one undifferentiated threat. It ends where the scale does, at six degrees, with the most severe outcomes the research describes.