Harry Potter and the Deathly Hallows by J. K. Rowling

Harry Potter and the Deathly Hallows is the seventh and final of the Harry Potter novels written by British author J. K. Rowling. The novel Harry Potter and the Deathly Hallows chronicles the final confrontation between the wizards Harry Potter and Lord Voldemort. Following Dumbledore's death, Voldemort continues to gain support and increase his power. When Harry turns seventeen, the protection he has at his aunt and uncle's house will be broken. Before that can happen, at Mad Eye Moody's suggestion, Harry flees to the Burrow with his friends, many of whom use Polyjuice Potion to impersonate him so as to confuse any Death Eaters that may attack. They are indeed attacked shortly after leaving Privet Drive; Mad Eye is killed, and George Weasley wounded, but the rest arrive safely at the Burrow. Harry, Ron, and Hermione know they cannot return to Hogwarts School for their seventh year. Instead, they decide to finish the quest Dumbledore started: to hunt and destroy Voldemort's remaining Horcruxes, objects in which he has hidden parts of his soul for the purpose of being immortal. They isolate themselves to ensure their friends and families' safety. They have little knowledge about the remaining horcruxes except the possibility that two are objects once belonging to Hogwarts founders Rowena Ravenclaw, Helga Hufflepuff and a third may be Nagini, Voldemort's snake familiar. The whereabouts of the two founders' objects is unknown, and Nagini is presumed to be with Voldemort. As they search for the Horcruxes, the trio learn more about Dumbledore's past ... (Summary by Wikipedia)