In March 1968 a Soviet submarine of the G-II class was lost with all hands, 16,500 feet below the surface of the Pacific Ocean. On 8 August 1974 ... [redacted] that submarine was brought to the surface in ... [redacted] a recovery system designed and developed specifically for that mission. The story of the more than six years intervening is the story of Project AZORIAN, that is, the story of the Hughes Glomar Explorer. AZORIAN ranks in the forefront of imaginative and bold operations undertaken in the long history of intelligence collection. It combined immense size and scope, advanced technological development, complex systems engineering and testing, unusually severe cover and security requirements, a demanding mission scenario in an unforgiving marine environment, the potential for a serious confrontation with the Soviet Union, a difficult and technically unusual exploitation phase, and high cost.