The 1960s. Soviet intelligence learns about US plans to strike from military bases located in Germany. Brezhnev understands that a retaliatory ultimatum will be the beginning of a nuclear catastrophe, so he decides to take the risk of concluding a secret agreement with German Chancellor Willy Brandt. To do this, he recruits former front-line soldier Vyacheslav Vardanov and German journalist Valery Pletnev. Together, they will complete an unprecedented mission, on the success of which the fate of the entire world depends.