In October 1962, the world went to the brink of Armageddon. This study provides an archive-based account of the Cuban missile crisis from the British perspective. The diplomatic, military and intelligence dimensions of British policy are scrutinized. New material is presented and existing interpretations of UK-US relations at that crucial moment are reassessed. The book contributes a new aspect to the literature on the Cuban missile crisis by exploring where the views of Washington and its closest ally converged and diverged.