Harry Potter and the Half-Blood Prince

With Voldemort at large, Dumbledore gives Harry private lessons using memories from Tom Riddle's past. In Potions, Harry uses an old textbook full of notes by the "Half-Blood Prince" and tops the class. He suspects Draco Malfoy has become a Death Eater on a mission. With Slughorn's real memory, Harry learns about Horcruxes, objects where Voldemort hid pieces of his soul. He and Dumbledore go after one in a cave, and Dumbledore comes back weak. On the Astronomy Tower, Draco disarms Dumbledore but can't kill him; Snape does. While fleeing, Snape reveals he's the Half-Blood Prince. The locket from the cave was a fake signed "R.A.B." After the funeral, Harry decides not to return to Hogwarts and to hunt the remaining Horcruxes.

1. ChangeThe Burrow burns only in the film

   The film adds a Death Eater attack on the Burrow at Christmas, with the house set on fire. It never happens in the book.

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2. ChangeFewer trips into the Pensieve

   In the book, Dumbledore shows Harry memories of the Gaunt family and Voldemort's mother, Merope. The film keeps only the orphanage and the Slughorn conversation.

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3. ChangeHarry isn't frozen on the tower

   In the book, Dumbledore freezes Harry under the Invisibility Cloak, so he watches everything unable to move. In the film, Dumbledore just tells him to hide below.

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4. ChangeNo battle in the castle

   In the book, Death Eaters fight the Order and the D.A. inside Hogwarts before the tower scene. In the film it's reduced to Bellatrix wrecking the Great Hall.

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5. ChangeDumbledore's funeral was cut

   The book ends with Dumbledore's funeral at Hogwarts. The film skips the ceremony and closes with the trio on the tower, watching Fawkes fly off.

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