Countdown to Zero traces the history of the atomic bomb from its origins to the present state of global affairs: nine nations possessing nuclear weapons capabilities with others racing to join them, with the world held in a delicate balance that could be shattered by an act of terrorism, failed diplomacy, or a simple accident. Written and directed by acclaimed documentarian Lucy Walker, the film features an array of important international statesmen, including President Jimmy Carter, Mikhail Gorbachev, Pervez Musharraf and Tony Blair.