Harry Potter and the Half-Blood Prince is the sixth book in J.K. Rowling's Harry Potter series. In this novel, Professor Snape makes an unbreakable vow to protect Harry Potter's rival, Draco Malfoy. Harry and Dumbledore look into memories in an attempt to learn more about Voldemort, and it is unveiled that he has been placing parts of his soul in objects called Horcruxes that must be destroyed if Voldemort is to be defeated.
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