Imagine waking in a village where the buildings are untouched but nearly every living thing, every human, animal, and insect, lies dead in perfect silence. Reporters described the scene as the aftermath of a neutron bomb. But this was no weapon and no supernatural event, just a natural geological catastrophe that struck without warning.

This episode dives into the Lake Nyos disaster of August 21, 1986, in Cameroon, a limnic eruption that released a suffocating cloud of carbon dioxide. We explore the bizarre physics that turned a tranquil crater lake into a silent killer, the harrowing survivor accounts, and the brilliant engineering used to disarm the lake. It matters because the Earth holds quiet, invisible threats we are only beginning to understand.

• How a freshwater lake trapped hundreds of thousands of tons of CO2 with no sal ...