Sofia. Agents of a foreign intelligence service receive orders to get hold of important secret documents from the Ministry of War. For this purpose, they recruit a girl working in a nightclub. On their instructions, she is acquainted and has an affair with a staff officer from the ministry. The sudden love between the two frustrates the spies' plans. The girl reveals the plot to her lover who tries to arrest the spies. During the chase, they kill the officer and the girl in a hotel room.