Harry Potter dreams of Frank Bryce, who is killed after overhearing Lord Voldemort discussing plans with Peter Pettigrew and another man. Harry attends the Quidditch World Cup between Ireland and Bulgaria with the Weasleys, but after the game Death Eaters terrorise the spectators, and the man who appeared in Harry’s dream summons the Dark Mark.
At Hogwarts, Albus Dumbledore introduces ex-Auror Alastor “Mad-Eye” Moody as the new Defence Against the Dark Arts teacher. He also announces that the school will host the legendary event known as Triwizard Tournament, in which three magical schools compete against each other in a very deadly competition by facing three dangerous challenges. The Goblet of Fire selects “champions” to take part in the competition: Cedric Diggory of Hufflepuff representing Hogwarts, Viktor Krum representing the Durmstrang Institute from Eastern Europe, and Fleur Delacour representing Beauxbatons Academy of Magic from France. The Goblet unexpectedly also chooses a fourth champion: Harry Potter. Dumbfounded, Dumbledore is unable to pull the underage Harry out of the tournament, as the Ministry official Barty Crouch Sr. insists that the champions are bound by a contract, and therefore, Harry is invited to compete. This makes Harry’s best friend Ron Weasley jealous of him.
For the tournament’s first task, the champions must each retrieve a golden egg guarded by a dragon. After summoning his broomstick, Harry succeeds in retrieving his egg, which contains information about the second challenge. Shortly after, another event known as the Yule Ball dance takes place; Harry’s crush Cho Chang attends with Cedric, and Hermione Granger attends with Viktor, which makes Ron jealous of Viktor. During the second task, the champions must dive underwater to rescue their mates. Harry comes out in third place, but is placed second behind Cedric due to his “moral fibre” after saving Fleur’s sister Gabrielle as well as Ron. Afterwards, Harry finds the corpse of Barty Crouch Sr. Harry visits Dumbledore at his office, and while waiting for him, he discovers a Pensieve, which holds Dumbledore’s memories. Inside it, Harry witnesses a trial in which Igor Karkaroff (Durmstrang Institute’s Headmaster) confessed to the Ministry of Magic names of other Death Eaters, after Voldemort’s defeat. He named Severus Snape as one, but Dumbledore defended him; he then named Barty Crouch Jr. This left Barty Crouch Sr. devastated, and his son was imprisoned in Azkaban. After exiting the Pensieve, Harry deduces that the man he has seen in his dreams with Voldemort is Barty Crouch Jr.
In the third and final task, the champions enter a hedge maze and must reach the Triwizard Cup. Viktor, under the influence of the Imperius Curse, incapacitates Fleur. After Harry saves Cedric when the maze attacks him, the two claim a draw and together grab the cup, which turns out to be a Portkey and transports the two to a graveyard, where Pettigrew and Voldemort are waiting. Pettigrew kills Cedric with the Killing Curse and performs a ritual using a bone of Voldemort’s father, Pettigrew’s flesh and Harry’s blood, which rejuvenates Voldemort, who then summons the Death Eaters. Voldemort releases Harry in order to beat him in a duel to prove he is the better wizard. Harry, unable to defend himself, tries the Expelliarmus charm at the same moment that Voldemort attempts the Killing Curse. Their wands do not work against each other, and Voldemort’s wand is forced to disgorge the last spells it performed. This results in shadow impressions of the people he murdered appearing in the graveyard, including Harry’s parents and Cedric. This provides an ample distraction to Voldemort and his Death Eaters, allowing Harry to escape with Cedric’s body by grabbing the Portkey.