Resurrecting a necropost rather than start a new one. I just watched a documentary on the Smithsonian Channel, titled
'The Spy in the Hanoi Hilton'. I have read quite a bit of Adm. Stockdale's heroics resisting the NV during his time as a POW but was unaware that he was "recruited" as a spy via his wife's letters and was able to pass on information to the CIA and ONI. From what the documentary said, this was not disclosed until the early 1990's, I've never heard of it. A great watch if the Smithsonian Channel is on your cable roster. Much of the show was also told by his son and widow. The link below contains clips from the hour long documentary.
https://www.smithsonianchannel.com/s...lton/0/3419642