If a bunch of people have the same exact memory of any given thing, that’s a pretty foolproof way to confirm the accuracy of said memory. Not if you’re talking about Tom Cruise wearing sunglasses during his iconic Risky Business dance scene, or the Monopoly man (whose name is Rich Uncle Pennybags, by the way) wearing a monocle, or any other occurrence of the Mandela effect. The phenomenon—so named because of the widespread yet erroneous belief that Nelson Mandela passed away in prison in the 1980s—describes a false memory shared by multiple people. On this episode of The List Show, Mental Floss host Justin Dodd is covering some of the strangest examples, along with leading theories to explain each one. For future fascinating videos, be sure to subscribe to the Mental Floss YouTube channel here.