What happens in Harry Potter book 7?

Harry Potter and the Deadly Hallows, the seventh and final novel in the Harry Potter series, begins with Harry, Hermione, and Ron attempting to recover Horcruxes, pieces of Voldemort's soul, in order to destroy him. They are aided by Dumbledore's Army, a group of students and teachers who are loyal to the late headmaster of Hogwarts. Together, they face dangerous challenges, including the pursuit of Voldemort and his Death Eaters, the Ministry of Magic's attempts to control Hogwarts, and the betrayal of one of their own. Along the way, Harry learns more about his past and his connection to Voldemort, leading to a final, epic confrontation between them.

Here are the main events of Harry Potter and the Deadly Hallows:

- Harry, Hermione, and Ron begin their quest to destroy the Horcruxes.

- They infiltrate the Ministry of Magic to retrieve a locket Horcrux and encounter several obstacles, including Death Eaters and traps.

- Harry has visions of Voldemort's past, which reveal his ties to the wizarding world and his motivations.

- The trio finds a copy of The Tales of Beedle the Bard, a children's book that holds clues to destroying Horcruxes.

- They return to Hogwarts, which has been taken over by Voldemort's supporters.

- Harry's friends and supporters form Dumbledore's Army and prepare to defend the school against Voldemort and his forces.

- Harry learns more about the Deathly Hallows, three legendary objects said to bestow immense power on their possessor.

- The Battle of Hogwarts begins, and Harry, Hermione, and Ron face off against Voldemort in a final showdown.

- Harry discovers the true meaning of the Deathly Hallows and uses this knowledge to defeat Voldemort once and for all.

The novel concludes with Harry, Hermione, and Ron, alongside their allies, celebrating the defeat of Voldemort and starting a new chapter of their lives.