The book opens with a description of the unprecedented 2021 heat wave in the Pacific Northwest. Glaciers melted rapidly, leading to floods and massive sediment plumes visible from space. Salmon suffered mass die-offs due to warmer waters lacking oxygen. Vegetation wilted, trees experienced internal damage, and wildlife displayed desperate survival behaviors while pests like pine bark beetles thrived, accelerating forest destruction. Urban areas exposed significant disparities: Poorer neighborhoods without trees recorded much higher temperatures than affluent, green areas. Human casualties were high, especially among the elderly and isolated without access to cooling systems. Lytton, British Columbia, was almost destroyed by a wildfire ignited during the heatwave.

Goodell challenges the perception of heat as manageable or positive, depicting extreme heat as a destructive force intensified by human-induced climate change through fossil fuel consumption. He believes that heat is the primary driver of climate crises, leading to secondary effects like sea-level rise and wildfires. Technological adaptations exist but are often insufficient and out of reach for poorer populations, increasing social and economic inequalities. With ongoing carbon emissions causing global temperatures to rise, vast regions of the Earth may become uninhabitable, threatening ecosystems and human civilization.