Operation Ivy Bells was an American secret mission launched by the US Navy, the NSA, and the CIA, whose objective was to place wiretaps on Soviet underwater communications lines to collect as much information as possible from their opponents during the Arms Race.
To achieve this goal, the Navy heavily modified USS Halibut with state-of-the-art sensors and equipment that no other submarine of its time had.
For over ten years, the United States wiretapped Soviet communications cables in the Sea of Okhotsk with a unique recording device deployed by Navy divers.
It would be until 1980 that the Soviets found out they were being spied upon, and the tip came from within the US...
