While trying to cross the State border of the USSR a resident of one of the Western intelligence services was detained and committed suicide who wanted to take out from Soviet territory a film shot at one of the defense facilities From abroad they send for a duplicate of the film the granddaughter of one of the closest associates of the Basmachev leader Ibrahimbek who inherited from her grandfather a fierce hatred for the Soviet country and the son of a man who sold his homeland during the war years