Favorite conspiracies that turned out to be true?

For me its Hitler continues to live in New Swabia. Got proven when Indian Navy scientists disappeared on 8 January 1990 at the Humboldt Mountains.

MKUltra. They literally worked on lsd as a weapon, with the plan of spraying whole towns with it. Imagine the alternative reality where they would thibk its a good idea after the tests on soldiers. I would love wars in that case