Harry Potter and the Half-Blood Prince is six hundred and fifty pages of pure magic. Unfortunately, such a lengthy title means that its cinematic adaptation had to leave some details to the imagination. At least, that's the case if you haven't read the books. Harry Potter book connoisseurs debate on the quality of which Harry Potter films and their subsequent book details are matched on the screen.

The Half-Blood Prince is one of those books that had to be followed almost precisely since it has more than a few catalyst moments the drive Harry's story forward. Still, there are a few things that make those who have only enjoyed the films scratch their head in confusion. So, to clear things up, here are 10 things that happen in The Half-Blood Prince that only make sense if you've read the books.

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Why Snape Makes The Unbreakable Vow

The first scene in this film shows Snape in cahoots with Draco's mother, Narcissa, as well as Bellatrix Lestrange. You know, Bellatrix, the one who killed Sirius Black? Considering that Snape is also known up to this point to be a member of the Order of the Phoneix, it seems strange that Snape is in this company at all. The truth is, as soon as Voldemort returned, Dumbledore had Snape retake up his position as a double agent. Narcissa requested the meeting with Snape in order to protect Draco, as we all know. The reason that Snape relents is that, although Draco is meant to be the one to kill Dumbledore, Dumbledore has already made Snape agree to kill him before the curse on his hand spreads.

Why Apparating Makes Harry Sick

Michael Gambon as Albus Dumbledore and Daniel Radcliffe as Harry Potter

Dumbledore takes Harry on a few errands, the most important of which involves convincing Slughorn to take up his position as the Potions teacher at Hogwarts. In order to get from each place, Dumbledore has Harry grab onto his hand so that they can both Apparate. Apparating is a standard wizarding trait that witches and wizards learn while at school. Harry seems to feel nauseous during this process. This is because Harry hasn't taken his Apparition classes. Since magic can only be performed outside of school after the age seventeen, Hogwarts students must wait until their sixth or seventh years to learn to Apparate. Harry takes Apparition during his sixth year, so he eventually learns to accept the queasy feeling that comes with this bit of magic.

Why Draco Was Made A Death Eater

Draco Malfoy Dark Mark

Draco Malfoy has always been at the center of mischief when it comes to activities at Hogwarts. However, Draco returns on the Hogwarts Express in this film to be noticeably less animated. Audiences later learn that Draco has been given a special task by Voldemort; he has to kill Dumbledore. But why is Draco assigned this task? Why is he made a Death Eater at all?

After the events from Order of the Phoenix, Draco's father, Lucious, is found out by the Ministry of Magic. And being one of Voldemort's right-hand men earns wizards a strict cell in Azkaban, Voldemort recruits Draco as a way to punish Lucious for being caught and to see if Draco has what it takes to follow in his father's footsteps.

How Harry Gets The Half-Blood Prince Book

Harry would not have had the success he had during his sixth year if it weren't for this potions book. Besides earning him top marks in his potion's class for the first time ever, it also helped him disarm Draco, and it eventually helps him learn more about Snape's character. But just how did Harry end up with this book?

Harry never bought his own copy of Advanced Potion-Making because he assumed he would not qualify to take the next level class due to Snape's hatred of him. However, since Slughorn took over the class, Harry was able to reenlist in this study so that he could become an Auror. That's why he and Ron have to fight over the leftover school books in their potion's class.

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All About Voldemort's Family

Harry Potter Half-Blood Prince Tom Riddle Voldemort Orphanage

The reason, as the general audience must know by now, that Voldemort goes after Harry as a child is because of the infamous prophecy. However, the reason he chose him as his equal is because Voldemort also has Muggle heritage. The Half-Blood Prince is full of details about Voldemort's family history and his childhood that help audiences understand how he grew up to be one of the most malicious wizards of the era. His mother Merope Gaunt put a curse on Tom Riddle Sr., a Muggle who she loved deeply. Not wanting him to know of her magic, she put him under the Imperius Curse and gave him love potions in order to sustain their relationship. Riddle Sr. eventually finds out, though, and presumably leaves Merope while she is pregnant with Tom. Unable to live with herself, she leaves Tom on the footsteps of an orphanage.

Dumbledore's Burnt Hand

This is mentioned in passing, but only those who read the books are privy to its full implications. The ring that charrs Dumbledore's hand belongs to Voldemort's grandfather, Marvolo Riddle. Voldemort, naturally, used this family heirloom as a Horcrux. When Dumbledore traveled to Voldemort's mother's former home in Little Hangleton, he recognized that the stone in the ring is one of the Deathly Hallows. Hoping to resurrect his sister, Ariana, he put on the ring. This awakened the curse embedded into the Horcrux, marking the starting point for Dumbledore's slow death. After realizing his mistake and its inevitable outcome, Dumbledore asks Snape to be the one to kill him.

Harry and Ginny's Relationship

In the films, Harry and Ginny's relationship seems contrived and awkward. However, in the books, Harry begins to show interest in Ginny much early on, so their relationship seems more natural in the books. Ginny's character is showcased in a better light in the books. She joins the Gryffindor Quidditch team, is incredible with spells, and is very vocal in her opinions. Movie Ginny is a bit more subdued, making it seem unlikely that these two would ever pair up. Also, their first kiss actually happens at after the win the Quidditch Cup, and Ginny kisses Harry in front of the entire Gryffindor common room.

What Dumbledore Sees Inside The Cave

Ariana Dumbledore's portrait in Harry Potter and the Deathly Hallows Part 2

When Harry and Dumbledore set out to find Salazar Slytherin's locket inside the cave, Dumbledore is forced to drink a transparent liquid within the basin. He starts acting strangely and even begs Harry to kill him. Harry later finds out that Dumbledore is reliving the moment that his sister, Ariana, is killed. Audiences don't find out about Ariana until two films later, so this connection is understandably never made.

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The Inferi

The reason that Voldemort chose this desolate cave as a place to hide a Horcrux is because he used to hide out there as a child when others would bully him. As it turns out, it was also a prime location to use Inferi as a guard for his Horcrux. The Inferi are corpses that are reanimated with the use of Dark Magic. The Inferi act on the orders of whoever brought them back to life, seemingly being used as puppets with no mind of their own. These specific Inferi in the cave are the bodies of Muggles whom Voldemort killed specifically for this purpose.

Snape's Escape

Snape's escape after murdering Dumbledore is a bit lackluster in the films. Could he really get away with a slew of Death Eaters on Hogwarts grounds that easily? Well, in the books, his escape was not as smooth as the films make it out to be. When Draco releases the Death Eaters from the Vanishing Cabinet, they begin their stride to take over the school. It's then that the Order of the Phoenix members, Hogwarts staff, and Dumbledore's Army recruits start to defend the school in a fight that would later become known as the Battle of the Astronomy Tower. The Death Eater's hostile takeover provided a pivotal distraction to get Snape out of the school.

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