This episode begins at the slopes of Mount Tambora (Indonesia), where a devastating 1815 eruption altered the planet's average temperature by 2 degrees and caused several natural and social catastrophes throughout the northern hemisphere. Using this and other historical precedents, Rubio speculates about the catastrophic effects that a similar thermic alternation (anticipated by most scientists) could have in the coming decades. The episode travels to countries such as Algeria, Brazil, Egypt, Russia, Switzerland, the UK, and the US. It shows some of the history's worst droughts, floods, and pandemics, instances which, according to Rubio, demonstrate the fragility of societies in the face of climate change. The episode also examines, however, how the successful banning of CFCs to counter the hole in the ozone layer illustrates humanity's ability to face major systemic challenges.