A systems test in a Soviet graphite reactor goes out of control. The ensuing explosion releases enormous quantities of radioactive material, much of which spreads across huge swathes of Europe.
Not only the surrounding region in Ukraine is contaminated, wind currents blow radioactive particles further west, across much of Europe where they mix with rain and fall to the ground. At first officials try to cover up the reactor disaster. The population is not informed immediately and as a result cannot be evacuated. The rest of the world is left equally unaware of the danger. The impact of Chernobyl is still felt today. The number of deaths and the long-term health consequences are countless.