In October 1962, the world went to the brink of Armageddon. This study provides a new archive-based account of the Cuban missile crisis, providing the first detailed and authoritative account from the British perspective. The book draws upon new British and US archival material and recent scholarship in the west and the former USSR. The diplomatic, military and intelligence dimensions of British policy are scrutinised. New material is presented and existing interpretations of UK-US relations at this 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.