The Business Plot is an overlooked conspiracy that's directly relevant. The public would be told that FDR was sick and needed help from a sort of helper president (who would practically take over). When Smedley Butler, the front man for the coup, asked how they expected the public to go along with it, he was told: "we control the media. They'll believe anything we tell them". And indeed, after Butler defected, the whole affair was called a hoax in the media and Butler was vilified intensely, even though historians today can only admit that it was real, just not near fruition yet. This is one of those subjects of which even the Wikipedia page is helpful.

(Incidentally, this is relevant to the current situation where the president is going senile and is partially in deep fake mode. This was also preceded by an economic crisis (which warms people up to coups), as well as a lot of propaganda to rig the election, by making the public think it's necessary to have mail-in ballots, which enable fraud.)

The Wikispooks article I linked to references two Unwelcome Guests episodes. These are highly recommended (kudos if you get the joke). The website seems down right now, which happens rather frequently, unfortunately. I have these archived and I can upload them somewhere if you want.

There's a recent documentary called 2030 Unmasked. This one is good in that it brings him up to date regarding the covid psy-op without seeming hung up about it, since it's also, as the name implies, about the road to 2030. The subject is, of course, very politicized. Subjects that the media aren't touching currently are better as introductory material. Nonetheless, this one is also worth a try.