Jim Angleton dedicated his life to building and maintaining the CIA. He spent years manipulating people and policy from his self-labeled "wilderness of mirrors," motivated by his own paranoia, and informed by an opportunistic Russian defector named Anotoli Golytsin. Eventually, despite his monumental efforts to cover his tracks, Angleton's chickens came home to roost.
Sources:
The Ghost: The Secret Life of CIA Spymaster James Jesus Angleton, by Jefferson Morley
https://amzn.to/3xgHDfS
https://www.brookings.edu/blog/brookings-now/2015/05/06/40-years-ago-church-committee-investigated-americans-spying-on-americans/
https://www.politico.com/story/2017/01/church-committee-established-jan-27-1975-234079
https://www.muckrock.com/news/archives/2017/oct/19/angleton-return/
https://jfkfacts.org/what-angleton-told-jfk-investigators-behind-closed-doors/
https://www.thedailybeast.com/my-lunch-with-the-spider-who-nearly-wrecked-the-cia
https://spartacus-educational.com/SSangleton.htm