The first mission is a flashback to April 17, 1961. Mason then recalls several events from the past in an attempt to answer their questions, setting up the missions of the game.
Mason awakens strapped to a chair in a room filled with monitors, bombarded with questions by two unknown interrogators about a numbers broadcast. Much of the Call of Duty: Black Ops campaign is told through the eyes of SOG and CIA operative Alex Mason, primarily through flashbacks. Furthermore, the campaign's playable characters now speak while being controlled by the player, a first for the entire Call of Duty series as a whole. The game also introduced several new features, such as dive-to-prone and the available use of a flashlight on certain weapons. Players play from the perspective of Captain Alex Mason of the MACV-SOG, Jason Hudson of the CIA, and Russian-born soldier Viktor Reznov of the Red Army. Call of Duty: Black Ops differs from most previous installments, which would involve a usual three-country campaign while Call of Duty: Black Ops features two playable countries (Russia and the USA), but only has an American campaign.