The official narrative is that over 200 huge buildings were built for the Chicago Worlds Fair only to be torn down a few years later. Everyone believes that story, even though they wouldn't have been able to even complete the foundations of the buildings in time for the fair with 1893 machinery.
(www.youtube.com)
Ancient Civilizations
Exactly how i would do it if i were an evil conspiracy covering up some mass extinction event... or potentially the actual rapture and was intent on repopulating... is it possible that the dark ages were actually the 1000yr reign of christ on earth and these civilizations are what was left after the true christians were taken to heaven? Maybe we are descendants of the leftover people. Also explains why (they) seem to control everything even though they seem incapable of keeping things from constantly deteriorating...
If that is the case, then this is the part where satan is loosed for a season.
And I'm not so sure the good guys are the leftovers -- there are a couple of different theories, one of which is that the bad guys disappear, not the good guys.
Maybe that is yet to happen?
I can imagine someone flipping a switch or sending out a signal and everyone who has received a certain formulation in their jab just...vanishes.
Poof!