The film tells about one of the Soviet counterintelligence operations "Smersh", which began in 1944 and ended in 1947.It was a deadly confrontation between the Soviet counterintelligence and foreign intelligence agencies, continue after the defeat of Nazi Germany. The focus of the film: a long time remaining classified as secret heroism of our scout, daily and hourly, to risk their lives working in an environment where failure and betrayal - ordinary event, continued his mission even after charges of treason.Four film series "Legend of the traitor" covers the main events of four years of desperate struggle, full of heroism and betrayal, despair and hope, hatred and love.