Harry Potter, Hermione Granger and Ron Weasley enter their fourth year at Hogwarts school. First, in a graveyard attached to an old country house; the gardener Frank Bryce awakes in his cottage to see a light on in the house. He investigates the light, and finds Lord Voldemort and Peter Pettigrew discussing plans with an unidentified man; Voldemort kills Frank. Harry awakes at The Burrow before departing with the Weasley family and Hermione for the Quidditch World Cup. After the introduction to the game, there is a temporal jump to that evening, when the camp is attacked by Death Eaters. Harry and the others run away from the scene wherein Harry witnesses the Dark Mark being cast into the sky by an unknown man (David Tennant); the Death Eaters disperse when the Dark Mark appears in the sky. Harry is accosted by a Ministry of Magic official who accuses the trio of having conjured up the Dark Mark. After the misunderstanding is cleared up Mr. Weasley tells Harry about the Death Eaters.
Harry, Ron, and Hermione arrive at Hogwarts, where they find that the school will be hosting the Triwizard Tournament, a legendary event in which one wizard each from two rival schools and Hogwarts compete in three dangerous tasks. Dumbledore reveals the Goblet of Fire, a magical cup which acts as an impartial judge to select candidates. The candidates are revealed to be Cedric Diggory from Hogwarts, Viktor Krum from Durmstrang, and Fleur Delacour from Beauxbatons. The goblet then unexpectedly announces a fourth champion, Harry, although he did not enter his name and is under the age limit set by the Ministry of Magic. Harry's entry into the Tournament incites jealousy and suspicion from his fellow students, including a breakdown of his friendship with Ron. Dumbledore asks the new Defence against the Dark Arts professor, Alastor Moody, to keep an eye on Harry.
In the first Triwizard task, each of the four champions must retrieve a golden egg being guarded by a dragon. Harry casts a summoning charm to bring his Firebolt into the arena, but the dragon breaks free of its chains and chases Harry through the Hogwarts grounds. Harry retrieves the egg, which is said to contain a clue about the second task, though only a horrible screeching emerges when he opens his egg. With help from Cedric Diggory, and Moaning Myrtle, Harry discovers he must open the egg underwater. Harry does so in the prefects' bathroom and hears the clue clearly; it informs him that the merpeople will take something of Harry's and that he must retrieve it from the lake in the Hogwarts grounds.
A traditional part of the Triwizard tournament is the Yule Ball. Harry asks Cho to go with him, but discovers that Cedric Diggory has already asked her. Hermione declines Ron's insensitive invitation, but does not reveal who her date is. Harry and Ron do not find out until the Yule ball that it is Krum himself who has invited her. Eventually, Harry asks Parvati Patil, who accepts; her sister Padma partners Ron. Although Hermione greatly enjoys the ball, Harry and Ron do not. Ron, who is particularly jealous of Krum, accuses Hermione of "fraternising with the enemy," leading to a serious row between the two characters.
In the second Triwizard task, each champion must find and save someone close to them who is now chained underwater. Harry swallows Gillyweed, which allows him to breath underwater, then begins searching for what has been taken from him. Harry finds Ron, Hermione, Cho Chang, and Gabrielle Delacour, Fleur's sister, catatonic and chained to a rock with thousands of merpeople guarding them. Harry cuts Ron free, hesitates, and then moves to cut free Gabrielle after realizing that Fleur, who had been attacked by Grindylows, will not be able to save her sister. Though the merpeople protest, Harry begins swimming to the surface, pulling Ron and Gabrielle with him. On the way, Harry is viciously attacked by a herd of Grindylows. He pushes Ron and Gabrielle upwards, draws his wand and scatters the Grindylows. He then propels himself to the surface using a spell, but still finishes outside the task's one hour time limit. Despite this, he is awarded second place in the trial because he was delayed by his decision to risk himself to free Gabrielle.
For the third task, the Triwizard cup is placed inside a large maze whose magical hedges are capable of attacking the champions as they attempt to reach it: the first champion to touch the cup will be declared the winner. Harry and Cedric reach the cup together and decide to claim a draw, both touching the cup at the same time. The cup turns out to be a portkey, which transports the two to a graveyard, where Pettigrew appears carrying Voldemort. Upon Voldemort's command, Pettigrew kills Cedric and traps Harry against an enchanted tombstone. Pettigrew takes blood from Harry's arm and mixes it with other ingredients to restore Voldemort. Voldemort tortures Harry as he explains the story of "The Boy Who Lived" to his assembled Death Eaters. The two duel, but Harry escapes when his wand unexpectedly caused Voldemort's to disgorge the spirits of the people Voldemort has killed, who protect Harry as he escapes and takes Cedric's dead body back to Hogwarts. Moody takes Harry to his office and starts interrogating Harry about what took place in the graveyard, Harry realizes something is wrong when Moody asks about the graveyard, though Harry had not yet mentioned it. Dumbledore, Snape, and McGonagall burst in the room and stun Moody; he begins to change shape as they watch and quickly transforms into Barty Crouch Junior, who has been impersonating Moody all year in order to ensure that Harry was entered into the Triwizard Tournament as part of Voldemort's plan to regenerate himself using Harry. The school year ends as the foreign schools depart after Dumbledore exhorts them to stand together against Voldemort.
Harry, Ron, and Hermione arrive at Hogwarts, where they find that the school will be hosting the Triwizard Tournament, a legendary event in which one wizard each from two rival schools and Hogwarts compete in three dangerous tasks. Dumbledore reveals the Goblet of Fire, a magical cup which acts as an impartial judge to select candidates. The candidates are revealed to be Cedric Diggory from Hogwarts, Viktor Krum from Durmstrang, and Fleur Delacour from Beauxbatons. The goblet then unexpectedly announces a fourth champion, Harry, although he did not enter his name and is under the age limit set by the Ministry of Magic. Harry's entry into the Tournament incites jealousy and suspicion from his fellow students, including a breakdown of his friendship with Ron. Dumbledore asks the new Defence against the Dark Arts professor, Alastor Moody, to keep an eye on Harry.
In the first Triwizard task, each of the four champions must retrieve a golden egg being guarded by a dragon. Harry casts a summoning charm to bring his Firebolt into the arena, but the dragon breaks free of its chains and chases Harry through the Hogwarts grounds. Harry retrieves the egg, which is said to contain a clue about the second task, though only a horrible screeching emerges when he opens his egg. With help from Cedric Diggory, and Moaning Myrtle, Harry discovers he must open the egg underwater. Harry does so in the prefects' bathroom and hears the clue clearly; it informs him that the merpeople will take something of Harry's and that he must retrieve it from the lake in the Hogwarts grounds.
A traditional part of the Triwizard tournament is the Yule Ball. Harry asks Cho to go with him, but discovers that Cedric Diggory has already asked her. Hermione declines Ron's insensitive invitation, but does not reveal who her date is. Harry and Ron do not find out until the Yule ball that it is Krum himself who has invited her. Eventually, Harry asks Parvati Patil, who accepts; her sister Padma partners Ron. Although Hermione greatly enjoys the ball, Harry and Ron do not. Ron, who is particularly jealous of Krum, accuses Hermione of "fraternising with the enemy," leading to a serious row between the two characters.
In the second Triwizard task, each champion must find and save someone close to them who is now chained underwater. Harry swallows Gillyweed, which allows him to breath underwater, then begins searching for what has been taken from him. Harry finds Ron, Hermione, Cho Chang, and Gabrielle Delacour, Fleur's sister, catatonic and chained to a rock with thousands of merpeople guarding them. Harry cuts Ron free, hesitates, and then moves to cut free Gabrielle after realizing that Fleur, who had been attacked by Grindylows, will not be able to save her sister. Though the merpeople protest, Harry begins swimming to the surface, pulling Ron and Gabrielle with him. On the way, Harry is viciously attacked by a herd of Grindylows. He pushes Ron and Gabrielle upwards, draws his wand and scatters the Grindylows. He then propels himself to the surface using a spell, but still finishes outside the task's one hour time limit. Despite this, he is awarded second place in the trial because he was delayed by his decision to risk himself to free Gabrielle.
For the third task, the Triwizard cup is placed inside a large maze whose magical hedges are capable of attacking the champions as they attempt to reach it: the first champion to touch the cup will be declared the winner. Harry and Cedric reach the cup together and decide to claim a draw, both touching the cup at the same time. The cup turns out to be a portkey, which transports the two to a graveyard, where Pettigrew appears carrying Voldemort. Upon Voldemort's command, Pettigrew kills Cedric and traps Harry against an enchanted tombstone. Pettigrew takes blood from Harry's arm and mixes it with other ingredients to restore Voldemort. Voldemort tortures Harry as he explains the story of "The Boy Who Lived" to his assembled Death Eaters. The two duel, but Harry escapes when his wand unexpectedly caused Voldemort's to disgorge the spirits of the people Voldemort has killed, who protect Harry as he escapes and takes Cedric's dead body back to Hogwarts. Moody takes Harry to his office and starts interrogating Harry about what took place in the graveyard, Harry realizes something is wrong when Moody asks about the graveyard, though Harry had not yet mentioned it. Dumbledore, Snape, and McGonagall burst in the room and stun Moody; he begins to change shape as they watch and quickly transforms into Barty Crouch Junior, who has been impersonating Moody all year in order to ensure that Harry was entered into the Triwizard Tournament as part of Voldemort's plan to regenerate himself using Harry. The school year ends as the foreign schools depart after Dumbledore exhorts them to stand together against Voldemort.