Harry, protesting all the way, is made to compete in the TriWizard Tournament. Hermione sticks by him and manages to get him to give an interview to the Daily Prophet which Skeeter writes up as a sympathetic piece, empathizing the danger Harry is in, and asking 'is this is a plot to kill the Boy Who Lived?' When there is a deluge of Owls protesting Harry being entered Dumbledore has to give a return interview wherein he explains the Cup is a magical contract and Harry has to compete. He does promise to tighten security at Hogwarts though.
Wanting to have nothing to do with it at all Harry does no prep for the First Task- even wearing the 'Diggory is the True Champion' badges (without the Potter stinks bit). When Bill warns him about the Dragons Harry simply shrugs and wanders off- though he does warn Cedric.
First Task! After the excitement of the other Champions daring moves to get the egg the crowd is rather disappointed by the sight of Harry Potter reading a book on a rock. The boy occasionally hisses at the Dragon, who simply looks at him non-hostile. After three hours of this most have left the stands in boredom. The few that remain are finally rewarded by the Dragon lowering her head to the floor and sorta hissing back at Harry. After a few hours of conversation in parcel tongue- which is only kind of a Dragon language she understands what Harry wants and hands the Champion the fake egg.
Frustratingly Harry still wins points for successfully completing the task in a daring, if dull, way. Harry does not care.
Second Task! After a successful Yule Ball with Hermione - they are both ignoring Ron now. Cedric informs Harry how to discover the clue to the 2nd task, but Harry does not bother. While he has his pride, he didn't want to be in this Tournament, and he is not going to even try. When a frustrated Moody all but tells him the clue Harry nods along and gets away from the smelly old man. Once it was obvious that Harry was not going to find the answer, Moody arranges to summon Dobby to the staff room, and then mentions the task and Gillyweed in conversation with Professor McGonagall. Dobby, as expected, steals some Gillyweed from Snape's stores and presents it to Harry, who thanks Dobby, but can't think why he'd need it, and gives it to Neville.
On the morning of the Task, Harry and co are down by the lake. Harry is put out that Hermione has not shown. Dumbledore than announces the Task details and then Victor, Cedric and Flur and gone into the lake in turn. Harry suddenly realizes where Hermione is. His Gryffindor nature kicks in and he attempts to dive in, then remembers he can't swim, or hold his breath for an hour. Dripping wet, he climbs out behind a huge rock that hides him from the crowd and summons Dobby, who is happy to retrieve Hermione- but informs the slightly panicking boy that she is in no danger anyway, the Merpeople are looking after them, and they will be returned. Harry instead waits and has a small lunch with Dobby while the others 'rescue' their people.
As predicted, Hermione is returned with Gabrielle, no harm done. Harry scores Zero for the Task. He does not care- though he has some explaining to do with Hermione...
Third Task! One month before the task the Champions are taken to see the growing maze. Afterwards Krum and Harry encounter a mental unstable, nearly naked Crouch. Harry summons Dobby to inform a teacher while he and Krum take Mr Crouch to the Infirmary. Part of the way there Moody appears, but given his physical state the teens reject his help. Moody then tries to Imperious them into letting him take Crouch- but Harry shrugs it off and Dobby arrives to blast 'Moody' off his Master. In the subsequent investigation, 'Moody' is exposed as Crouch Jr. and real Moody rescued. Crouch Snr is of course ruined, but he has a certain amount of sympathy.
The Third Task goes ahead- but given the recent situation, everything 'Moody' has touched is investigated. The plan to get Harry to the graveyard is uncovered in Crouch Jr's notes- but which graveyard and why is not mentioned. Instead a plan is hatched therein Harry would enter the Maze (as per his contract to compete), then while the other Champions compete for a replacement Cup, Harry and a select force of Aurors and Order members would touch the Portkey cup and see where it went.
The Battle of Little Hangleton was uneventful. Wormtail offered little defence of himself, and the Voldermort baby was unable to resist anyone. Nagini is killed in the fight. The Minister cannot deny the attempted return of Voldermort, or the continuing existence of Wormtail, so as a result Sirius is pardoned, and a through re-examination of old Death Eaters is begun- spearheaded by a very, very annoyed Moody. Fudge is driven from office by the public, and his replacement Kingsley Shacklebolt takes great joy in jailing Lucius Malfoy. Snape escapes jail but is driven from Hogwarts- not that he cares much, his debt was paid!
Cedric and Krum jointly win the Triwizard Cup, though their victory is slightly overshadowed by events elsewhere.