In 2009, paranormal researcher Fiona Broome was sitting in a green room at a science fiction and fantasy convention when a conversation began about South African politician Nelson Mandela. Several people in the room were absolutely convinced that Mandela had died in prison many years earlier. They even remembered his funeral. In fact, Mandela was still alive; he was actually released from prison in 1990 and went on to become South Africa’s president. He didn’t pass away until 2013.

According to Broome’s official website, someone in that green room — she says she’s not sure whether it was the security manager, her husband, or herself (and even if she was, who could trust their memory?) — coined the term “the Mandela Effect” right on the spot. It was meant to describe the phenomenon where a group of people share a distinct memory of some historical event that historical records state never took place. The term steadily gained traction on online, especially in places like Reddit, where people came to share and discuss memories that seemingly contradicted reality. Although the first Mandela Effects came from the realm of history, they were soon identified in other areas, including popular culture.

They are particularly prevalent in the world of movies, where people have vivid memories of endings that don’t exist, lines of dialogue that differ from their famous quotes, and of entire movies that were never made. Below are 10 notable examples of cinematic Mandela Effects. Wherever possible, we’ve tried to identify the source of the confusion — assuming it’s not, you know, mass migration of souls through alternate dimensions.

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