The clue he received in the film was from Bellatrix, who was in a frantic frenzy when she thought her vault was broken into. He is ultimately able to identify the cup as a Horcrux because of his ability to hear the piece of Voldemort's soul contained within them, an ability which is not present in the books.

How did they know the cup was in Bellatrix's vault?

Bellatrix as good as told him by freaking out when she saw the sword of Gryffindor. He didn't know which horcrux, but he had a very good chance to find a horcrux. It could not be the snake, neither the diary, nor the ring or the locket so he was down the diadem and the cup.

Did Bellatrix know she had a Horcrux in her vault?

At some point in time, Lord Voldemort gave Bellatrix Lestrange Hufflepuff's Cup, one of his Horcruxes, to keep safe in her vault, though he didn't tell her its true nature.

How did Harry know the cup was at Gringotts?

Harry knows from his conversations with Dumbledore that if a Horcrux is in the vault, it must either be the Hufflepuff cup or else an unknown object, so they have no choice but to look for the cup.

How did Harry know a Horcrux was in Hogwarts?

Harry had a vision soon after the Gringotts break-in. He saw the locations of all the Horcruxes. He was vindicated in the eyes of Ron and Hermione when he discovered that Hogwarts was the home of one of the Horcruxes.

Harry Potter is the Final Horcrux | Harry Potter and the Deathly Hallows Pt. 2

Did Voldemort realize Harry was a Horcrux?

Notably, Voldemort appeared to be entirely unaware of this split, as he later created a seventh Horcrux in his quest to have six, and continued to target Harry Potter despite him now holding part of Voldemort's own soul.

Did Dumbledore realize Harry was a Horcrux?

Dumbledore knew about Horcruxes. He knew how they were formed, what happened after that, etc. He probably got to know Harry was a Horcrux when he saw the Scar on Harry's forehead, but maybe he wasn't sure.

Why did Snape put the sword in Bellatrix Vault?

After the fall of the ministry, the death eaters would have discovered that Dumbledore intended for the sword to go to harry in his will - so Snape was ordered to hand it over to Bellatrix for protection. Snape gave them a fake and found a way to get the real one to harry.

Why is there no Gryffindor Horcrux?

Still, any Horcrux would be far more vulnerable than the Sword of Gryffindor. If the sword were to be imbued with a soul fragment and therefore turned into a Horcrux, it would no longer be indestructible but vulnerable to Fiendfyre and basilisk venom—two substances it would have otherwise absorbed in its natural state.

Where did the sword go when Griphook died?

This betrayal ultimately proved to be Griphook's own undoing, as he was murdered by Voldemort alongside the other Goblins who reported the Cup's theft to him and Griphook's death caused the Sword to vanish back into the Sorting Hat.

Why didn't Harry use Avada Kedavra on Bellatrix?

Harry never used the Killing Curse, Avada Kedavra, due to his moral stance against murder and his personal connection to its victims.

Why did Voldemort give Bellatrix a Horcrux?

This is proven by the fact that he didn't even suspect she had a Horcrux. Lucius was given one to smuggle it to Hogwarts under Voldemort's supervision but Bella was given the Cup for the sole purpose of protecting it because he trusted her.

Did Voldemort impregnate Bellatrix?

Delphini was born in secret at Malfoy Manor in early March 1998 as the result of a liaison between Bellatrix Lestrange and Lord Voldemort. On 2 May 1998, both of her biological parents were killed in the Battle of Hogwarts.

Why didn't they just show the goblin Bellatrix's wand?

They were asking because if she had Bellatrix's wand (which was stolen by Harry Potter) then she would be an accomplice of Harry. In the book, she gives them the wand and it alerts them that she is an imposter since the wand was known to be stolen. Harry then uses an imperius curse on the goblin in order to get in.

Why did Griphook betray Harry?

The goblin does not trust wizards and witches, which leads to his betrayal in Gringotts, and Griphook was bloodthirsty and relished the idea of lesser creature's pain.

Why does Bellatrix have two wands?

You may be looking for her original wand. Bellatrix Lestrange's second wand was possibly bought in 1998, but it is more likely Bellatrix stole it or made it. It may have been made by Ollivander as a prisoner. He was forced to make one for Peter Pettigrew, so the Death Eaters most likely had a supply of backup wands.

Would Harry have lived forever as a Horcrux?

Being a horcrux simply means that Harry had a piece of Voldermort's soul inside of him. That would not grant him immortality. Harry Potter after this part he is no longer a Horcrux, Voldemort destroyed his part of the soul that resided in the boy.

Why isn't Hermione affected by the Horcrux?

The simplest explanation of Hermione's resistance to the Horcrux's effects is her superior mental strength. Hermione proved herself once again when she withstood Bellatrix's Cruciatus Curse.

What was the hardest Horcrux to find?

Slytherin's locket

Beyond the ring, another heirloom was transformed into a Horcrux, and was one of the hardest to find and destroy.

Why didn't Hermione save Dobby?

Honestly, Hermione knew Dobby was a lost case... nothing could have revived Dobby after the attack or she would have definitely helped Harry with Dobby considering she was the girl who started S.P.E.W(Society for the Elfish welfare) and fought for elf rights. There was nothing to be done at that point.

Why was Bellatrix mad about the Sword of Gryffindor?

Bellatrix Lestrange believed Harry had broken into her vault at Gringotts after realizing Harry had the Sword of Gryffindor. Griphook lied to Bellatrix, telling her that the sword Harry had was a forgery.

Why didn't Dumbledore tell Harry how to destroy Horcruxes?

Dumbledore Never Really Had Time To Explain How To Destroy The Horcruxes. As much as Harry would have benefited from Dumbledore's knowledge of how to destroy the remaining five horcruxes, there was simply not enough time before his death to do so.

What happens to Umbridge?

After Voldemort's defeat by Harry at the Battle of Hogwarts and the restoration of the Ministry of Magic by the new Minister, Kingsley Shacklebolt, Umbridge was sentenced to life imprisonment in Azkaban for her crimes against Muggle-borns.

Did Severus love Harry?

In the Harry Potter and the Deathly Hallows movie, Snape showed how much he loved Harry, providing him with his memories and showing that he saw Lily in him, his last words echoing this: "You have your mother's eyes."

How did Dumbledore know Harry and Ron were under the cloak?

Behind the scenes

In a chat with fans on the-leaky-cauldron.org, J. K. Rowling answered a fan's question of why Albus Dumbledore was sometimes able to see Harry under the Cloak of Invisibility, explaining that he used the Human-presence-revealing spell with non-verbal magic.