It was an anxious wait for the radioactive cloud. It only reached the West days after the explosion of Unit 4 at the Chernobyl nuclear power plant. What the Soviet system initially tried to cover up during the Cold War turned out to be devastating A nuclear disaster with many victims turned out to be the nuclear accident in Chernobyl on April 26, 1986. The ARD documentary tells the story 40 years after the worst possible accident (GAU). Chernobyl 1986 – the disaster about the now seemingly strange time when communication took place via landline telephones and the danger was initially greatly trivialized.