Muggles' Guide to Harry Potter/Characters/Griphook

Overview
Griphook is a goblin who worked at Gringotts Wizarding Bank.

Philosopher's Stone
When Harry and Hagrid visit Gringotts to retrieve some money for Harry and the "you-know-what in vault seven hundred and thirteen" for Professor Dumbledore, it is Griphook who drives the cart that takes them down to the vaults. Griphook tells Harry that the deeper, high-security vaults will open only when stroked by a Gringotts goblin; anyone else trying it would simply get sucked through the door and would not be able to escape. He also says they check the vaults for that happening about once every ten years.

Deathly Hallows
When Harry, Ron, and Hermione are moving from campsite to campsite through the English countryside, another group of refugees briefly and unknowingly camps beside them. This other group, comprised of Dirk Cresswell, Ted Tonks, Dean Thomas, and the goblins Griphook and Gornuk, reveals that a group of students at Hogwarts had tried to steal the sword of Gryffindor from the Headmaster's office. The students had been punished, and the sword had been transferred to a safe at Gringotts. The goblins also revealed that the sword in Gringotts was a fake, a very good fake but not Goblin-made.

Harry, Ron, and Hermione are later picked up by a gang of Snatchers. It turns out that they have already captured some members of Griphook's group, killing Ted Tonks, Dirk Cresswell, and Gornuk. Harry finds himself tied to a pole with Griphook and Dean Thomas. All of them are transported to Malfoy Manor together so that the Snatchers can turn Harry Potter in to Voldemort for the reward. Bellatrix Lestrange sees that they are carrying the sword of Gryffindor, and prevents the Malfoys from summoning Lord Voldemort. She sends Harry, Ron, Dean, and Griphook down to a basement room and locks them in; they find that Luna Lovegood and Mr. Ollivander are already there, and Luna is able to get them free of their bonds. Bellatrix tortures Hermione to get her to tell where she got the sword. Hermione manages to tell her that they found it in the woods, and that it's a copy. Bellatrix says that the goblin will be able to tell that; Harry tells Griphook that he has to tell Bellatrix that the sword is a fake. Griphook, brought before Bellatrix, corroborates Hermione's story, and Bellatrix, relieved, summons Voldemort.

After a short battle in which the injured Griphook takes no part, Harry and Ron Apparate away to Shell Cottage, Harry carrying Griphook and holding on to Dobby. Dobby, who has been hit by a knife thrown by Bellatrix, dies, and Harry digs a grave for him by hand. Griphook, though injured, takes a very keen interest in what Harry is doing, as he has never before seen a "wand-carrier" who seemed at all interested in the feelings of Goblins or house-elves.

From Bellatrix's reaction at the sight of the Sword of Gryffindor, Harry has determined that she believes the true Sword is stored in the same place as something that is deeply valued by Voldemort, and guesses it to be the Cup of Helga Hufflepuff, which Voldemort has made into a Horcrux. Harry guesses this to be Bellatrix's vault at Gringotts, and discusses with Griphook how they might break into Gringotts, and what Griphook's price for helping them would be. Griphook is reluctant, as he does not want to be the agent of successful theft happening at Gringotts, but relents when Harry tells him that he is not doing this for wealth, but for a specific artifact which is crucial to their quest. They finally determine that Griphook will receive the sword of Gryffindor, which he believes belongs properly to the Goblins as it was originally made by them.

Riding on Harry's back under the Invisibility Cloak, Griphook provides guidance to Harry, Ron, and Hermione as they make their way into Gringotts, suborn one of the tellers, Bogrod by name, and have him take them to the deep vaults. There, they find that Bellatrix's treasure is protected by the Gemino and Flagrante curses, endlessly multiplying and becoming searing hot when touched. In their search for the Cup, they cannot help brushing against treasure, which starts spinning off worthless, burning-hot copies of itself. By the time Harry manages to locate and retrieve the Cup, the vault is waist-deep in burning gold and Griphook is completely buried. Harry pulls Griphook out of the pile of treasure, and has Bogrod re-open the vault door. As they spill out into the corridor, Griphook seizes the Sword of Gryffindor and runs to the approaching Goblin party, saying he's caught the thieves. Harry, Hermione, and Ron escape by climbing onto the back of the dragon protecting the vaults and flying out of the dungeons.

Relationships with Other Characters
He seems to be prejudiced against wizards, and uncaring if any get hurt during the execution of his and Harry's plans. Despite his being willing to work with Harry to recover the Cup Horcrux, his allegiance is not to Harry, but to the Sword; as soon as he considers his part of the bargain complete, he takes the Sword and leaves Harry, Hermione, and Ron to their fates.