In 1968, as all eyes were fixed on the Space Race, the Cold War superpowers were playing deadly chess in the world’s oceans, with nuclear submarines their most powerful, secretive pieces.

So, when the Russia’s K-129 disappeared on its third patrol, both sides were keen to trace the wreck. Soviet efforts alerted the US, who triangulated reports of an underwater explosion and within months found the hulk. 

What followed was one of the most remarkable exploits of the Cold War, as the US planned to salvage the submarine – armed with nuclear torpedoes and ballistic missiles – to gain its secrets. For security, the project, dubbed Azorian, was handled by the CIA, rather then the Navy, but it took six years to come to fruition, as a unique salvage vessel had to be built to raise the hulk at a cost of more than £1bn in today’s money. 

The project was only partially successful, as the K-129 broke up as it was raised, What was recovered is still an official secret, but six bodies, heavily irradiated, were buried at sea with military honours, and a film of the ceremony was later handed to the Russians. 

CIA staff tell their story in their own words for Azorian: The Raising of the K-129, which includes film of the wreck taken during the 1974 mission, and is the first full public account of the project.