
Harry finds Helena's ghost in Ravenclaw's common room and convinces her to tell him where the diadem is: in the Room of Requirement, where hidden things are stored. She activates the castle's magical protections and orders everyone to prepare for battle. Snape flees and McGonagall takes charge of the defense of Hogwarts. Snape tries to calm them down, but he is confronted by Professor McGonagall (Maggie Smith), who challenges him to a duel. Meanwhile, Voldemort and his army of Death Eaters arrive at Hogwarts and demand that Harry surrenders himself or they will attack. He learns from Luna Lovegood (Evanna Lynch) that there is a ghost of Ravenclaw's daughter, Helena (Kelly Macdonald), who knows where it is. Harry asks them to help him find another Horcrux: Rowena Ravenclaw's diadem, a tiara that enhances wisdom. Harry, Ron and Hermione enter Hogwarts through the passage and are greeted by their friends and former teachers, who are ready to fight for them. He reveals that he is part of a resistance movement led by Neville Longbottom (Matthew Lewis), who has been defying Snape (Alan Rickman), the new headmaster appointed by Voldemort. They are rescued by Aberforth Dumbledore, Albus Dumbledore's estranged brother, who owns a pub and has a secret passage to Hogwarts through a painting of his deceased sister Ariana. Harry realizes that another Horcrux is hidden at Hogwarts, so they Apparate to Hogsmeade, where they are detected by a magical alarm. They escape on a dragon that was guarding the vaults and fly to a lake, where Harry has a vision of Voldemort learning about their theft. However, Griphook betrays them and takes the Sword of Gryffindor, which they need to destroy the Horcruxes. They disguise themselves with Polyjuice Potion and manage to reach the vault, where they find the Horcrux: Helga Hufflepuff's cup.

They persuade Griphook, a goblin who was also captured by the Death Eaters, to help them break into Gringotts Bank, where they suspect that one of the Horcruxes is hidden in Bellatrix Lestrange's vault. Harry, Ron and Hermione are hiding at Shell Cottage, where they bury Dobby, the loyal house-elf who sacrificed his life to save them from Malfoy Manor.


The film begins with a dark and ominous scene, as Voldemort breaks into Dumbledore's tomb and steals the Elder Wand, one of the Deathly Hallows and the most powerful wand in existence.
