The Harry Potter and the Philosopher’s Stone, the first entry in a series of seven books telling the story of “the boy who lived” and Lord Voldemort, the darkest wizard of all.

The Harry Potter book series became a worldwide phenomenon, and it didn’t take long for Hollywood to set eyes on it and bring it to the big screen. The Harry Potter movie saga was released between 2001 and 2011, with the final book, Harry Potter and the Deathly Hallows, divided into two movies (and setting a trend for other fantasy/YA book series that made the jump to film). The movies were also a success and expanded the books’ fanbase, and while some elements, characters, and events had to be left aside, they also made way for various moments of foreshadowing, and there’s a very important one in Harry Potter and the Half-Blood Prince, which hinted at the twist of Voldemort creating not one but seven horcruxes.

Related: How Harry Potter Turned Lord Voldemort Into His Own Horcrux

Lord Voldemort (whose real name was Tom Marvolo Riddle) was a dark wizard whose purpose was to get rid of “mudbloods” (those wizards and witches who were muggle-born or half-blood) and take control of both The process to create a horcrux is very complex and involves committing murder, but that wasn’t going to stop Voldemort from creating a couple. Voldemort’s plans of creating horcruxes were revealed in flashbacks in Harry Potter and the Half-Blood Prince, and the twist of him creating seven was also hinted at in some of those memories.

An image of several petals in Harry Potter and the Half Blood Prince

In Half-Blood Prince, Dumbledore shares a memory with Harry of Riddle before he arrived at Hogwarts, in which Dumbledore met the young wizard at an orphanage. During that sequence, there’s a shot of seven rocks on the windowsill of Riddle’s bedroom, a subtle hint at him splitting his soul into seven parts to create the horcruxes years later. The seven horcruxes are confirmed later on after Dumbledore asks Harry to retrieve a memory of Riddle from Professor Slughorn that he knew would be key in their plans to defeat the Dark Lord, and after some trouble, Harry finally got that memory after drinking Liquid Luck. That memory showed that Riddle asked Slughorn about horcruxes, confirming to Dumbledore that he created more than one.

After a lot of dangers on their journeys to get all the horcruxes, Dumbledore, Harry, Ron, Hermione, and Neville (as he killed Nagini) destroyed them all, with Harry finally defeating Voldemort in Harry Potter and the Deathly Hallows. Just like the rocks on Riddle’s window, there are many other subtle moments of foreshadowing throughout the whole Harry Potter movie saga, but this might be one of the most important ones due to the purpose and impact of Voldemort’s horcruxes.

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