Cable tapping went wrong, suddenly had a cold bath..?
Maybe a Russian version of THIS:
https://www.amazon.com/Blind-Mans-Bluff-Submarine-Espionage-ebook/dp/B0089EMLGK/ref=sr_1_1?crid=3140ZWCZLGUVV&keywords=blind+man%27s+bluff+the+untold+story+of+american+submarine+espionage&qid=1562204149&s=gateway&sprefix=Blind+Man%27s+Bluff%2Caps%2C423&sr=8-1