Spring of 1941 . After Yugoslavia joined the "anti-Commintern" pact of Germany, Italy and Japan, a coup d'état took place in the country. The government of General Simovich comes to power, more sympathetic to Britain and the United States than to the Axis countries. For Hitler, the fate of Yugoslavia was decided, despite the fact that Simovic confirmed the commitment of his government to all previous agreements. German troops are drawn to the Yugoslav border. In order to prepare the ground for the invasion, a "trade delegation" of the standard-bearer Weesenmeier arrives in Zagreb, the capital of Croatia, in whose asset the coming to power in Slovakia of a government loyal to Germany . He also has similar tasks this time - to play on the national contradictions between Serbs and Croats and bring pro-German forces to power in Zagreb. The "delegation" includes the Soviet agent Sturmbanfhrer SS Stirlitz, who in the current situation has new tasks - undermining the activities of the Weesenmeier group .