During the height of the Cold War, the United States Navy executed one of the most audacious and physically dangerous wiretapping operations in human history. Deep within the heavily guarded, freezing waters of the Sea of Okhotsk, a specially modified American nuclear submarine located a vital underwater communications line connecting the Soviet Pacific Fleet to mainland command. Because the cable was unshielded, the NSA designed a massive, six-ton recording pod that could wrap around the line and capture unencrypted military traffic through magnetic induction, without ever physically piercing the casing. Deploying and retrieving these tapes required saturation divers to exit the submarine at crushing depths, working in total darkness while actively evading Soviet sonar patrols overhead. A single ruptured seal or misplaced anchor would have instantly triggered a devastating international incident. Plunge into the ultimate classified mission. Decode the extreme pressure physics, the bespoke acoustic engineering, and the sheer nerve required to steal Soviet military secrets from the bottom of the ocean.