What is the best real world ""plot twist"" in history?

Honestly, the whole story of Operation Mincemeat during the second world war is just insane. The british basically dressed up a dead body as a fake officer, planted some fake invasion plans on him, and just dumped him in the ocean. The germans totally fell for it and moved their entire defense strategy based on a lie. It’s like something straight out of a cheap spy movie, but the fact that it actually changed the course of the war blows my mind every time I think about it.

Another one that always gets me is the discovery of the tomb of Tutankhamun. Everyone thought the valley of the kings had been picked clean by grave robbers centuries ago. People were literally about to give up on the site when they stumbled upon the entrance under some old workmen's huts. It’s crazy to think that one of the most famous treasures in history was just sitting there right under their noses the whole time, completely untouched while everyone else was looking elsewhere.