As usual, I own nothing in the Harry Potter universe, JKR owns it all.
Harry Potter and his wife, Fleur (nee Delacour), were smiling, as they waited to enter the maze, the third and last task, in the Tri Wizard tournament. They had just told Fleur's parents that she was pregnant, and her family had been happy with the news.
Although Harry was slated to enter first, and Fleur last, he waited by the entrance for her, and they meandered through the maze, neither of them were focused on winning, both would be happy when the tournament was over. As far as they were both concerned, the only good thing that had come from their being entered in the tournament, was their forced marriage, due to the life debt created when Harry saved Fleur during the second task. The marriage, and the consumation thereof, had put Fleur in the family way, but even though they were young, with Harry still in school, they were happy. Harry, as he would now no longer the only blood member of the Potter family, Fleur, as it was a symbol of her love for him.
Eventually, after a surprisingly easy passage, they reached the cup, and they both grabbed it at the same time. They felt the pull of a portkey, and reappeared in a graveyard, their mood changed, as they noticed the name Riddle on most of the tombstones. Harry recognised it from the diary incident in his second year, and Fleur from his pensieve memories of that year. Fleur grabbed him, and was about to apparate them both back to Hogsmead, when Harry collapsed with a moan of pain.
Fleur bent over to speak to him, when they heard a voice state " Kill the spare". As she looked up, she saw the green light a killing curse coming towards her, it was too late to duck it, and it hit her in her abdomen, to her shock and relief, the curse bounced off of her and went straight back to the caster, a small balding man, who dropped the bundle he was holding in shock, as the curse came back and hit him. As the bundle hit the ground, there was a grunt of pain from it, and Harry immediately started feeling the pain in his scar diminish.
He looked up, worried that Fleur was dead, but saw instead that she was pinching herself, in shock that she was untouched by the curse.
They moved to the bundle, which Harry suspected to be Voldemort, and after discussion, they stunned it, and then transfigured it into a snail, which they then put into a small glass aquarium, transfigured from Pettigrew's body.
Holding Harry tightly to her, Fleur then apparated them both back to Hogsmead, and they walked back to the school. During the walk, they realised that the cup was spelled to carry the first person to touch it to the graveyard, they therefore suspected whoever placed it, or the person(s) who were last in the maze, before the champions had entered, as the one to to be supporting Voldemort.
As they had no faith in Dumbledore, and Harry had none in Fudge, the Minister, after the fiasco of Pettigrew's escape last year, Fleur put disillusionment charms on both of them, and holding hands, not to get separated, they went looking for her father, or Madame Bones.
After finding her father, and whispering to him to bring Madame Bones and Madame Maxine to the Beauxbaton carriage, they went there.
At the carriage, they explained to the three adults what had happened, leaving them believing that they had escaped without seeing anyone. They then told of their concern that whoever had set up the portkey was still there. Maxine stated that Professor Moody had been the one to place the cup, as well as being the last one in the maze.
Promising to keep an eye on him, the adults returned to the stands with the glass box with the snail being left in the carriage. Meanwhile the Potters, waited for a while, before following them, intent on telling everyone that they had just walked back from Hogsmead, after apparating there following the cup portkeying them to an abandoned graveyard.
When they reached the judges, they gave them the prepared story. There was promptly an argument as Karkaroff said that no cup, meant no Champion. Moody meanwhile tried to grab Harry, Madame Maxine promptly knocked him out with a punch. This stopped the arguments as everyone looked at her as she then tied him up. She stated that as the person to put the cup in the maze, he was her prime suspect. She then searched him, and having found and removed two wands from him, handed them to Madam Bones. While the other judges and the Minister were debating, to themselves if to stop her, Moody started changing before their eyes, and Bones muttered, "polyjuice".
Madam Bones promptly sent out a patronus message asking for aurors to come to the school and bring veritaserum to question an escaped prisoner. The Minister meanwhile was calling for a dementor to come and kiss the escaped prisoner. Madam Bones shouted " Belay that order, we need to find out what happened here, and giving him the kiss will not help us".
Harry, who had no desire to expose his pregnant wife to the dementor's effects, cast his patronus. The Minister's desire to get the dementor to the stunned figure on the ground became moot, as the dementor was being kept at bay.
Meanwhile Harry was asking, " Who is that" pointing at the unconscious man.
Madam Bones responded "Barty Crouch Junior, the problem however is not just who is he, it is that Barty Crouch junior is supposed to have died in 1982"
Harry muttered " Another man back from the dead"
Madam Bones looked at him "What do you mean by that statement"
Harry looked at her with a puzzled expression" Did neither the Minister or the Chief Warlock tell you that five of us saw Peter Pettigrew last year?"
Madam Bones said "No" and turned to the Minister and Dumbledore, "Well?".
The Minister muttered "They were confounded, I was not going to pass along nonsense"
Madam Bones responded "And which medical officer confirmed that they were confounded?"
The Minister snarled " There was no need for an examination, Professor Snape assured me that they were confounded"
Madam Bones sighed and ignored him.
Eventually, the aurors reached with the veritaserum and Crouch junior was interrogated in front of a number of witnesses.
The interrogation revealed a number of facts. The first was how he escaped, it had been arranged by his parents, with his mother taking his place. The second was that he had been helped to escape from his father by Pettigrew and a being he believed to be Voldemort. Next was the location of the real Moody, then the fact that he had spelled the cup to accept Harry's name. Last was the killing of his father and changing the Trophy cup to a portkey, in order to get Harry to Voldemort for a ritual. The last question was how Voldemort intended to imperius another group of followers. Crouch laughed as he said that none of the marked followers were imperiused to join or partake in the Death Eater activities, they were expected to return when the dark mark on their arms called them back. Although they could expect to be punished for having denied the Dark Lord and not looking for him.
At the end of the interrogation, Madame Bones had issued a number of orders. The most important was to get a team of aurors to go to the portkey destination, in order to capture Pettigrew and the alleged Voldemort. Another was that starting immediately, no prisoner visits were to be face to face. There would always be a barrier between visitors and prisoners. Lastly, she wanted all the alleged imperius victims to be brought in for "protection from a small group of apparently insane followers of Voldemort" She smiled to herself, as she planned to question them under veritaserum, to "ensure they were not a risk to other members of the group."
By the time the auror team came back from the graveyard, they had started questioning Harry and Fleur on their experience after they were portkeyed away. Harry stated that once they saw the graves marked Riddle, he told Fleur to apparate them away quickly. They heard someone coming, but did not wait to see or speak to them.
The team reported that no living persons were there, but they had seen a snake, which registered as magical and they had killed it when it attacked them. They had also found and brought back the trophy cup.
With the return of he trophy as proof of Harry and Fleur's statement that it had been used as a portkey and they had left it where it took them, the majority of the judges declared the competition over and that Harry and Fleur were joint winners.
Madam Bones then asked Dumbledore to stay behind, as she wanted to know how he was fooled by Crouch junior for nine months, especially after the insertion of a fourth member into a three person competition.
Harry, Fleur, her Headmistress and her family then asked if they could be excused, and left for the Beaxbaton carriage. There, the Potters and Delacours, collected the snail and glass case and flooed to the Delacour home in France. They then contacted the Delacours Healer to come and check on Fleur and Harry.
Upon her arrival, the Healer checked Fleur, confirmed the pregnancy and told her that both mother and child were in good health. After the Healer left, Harry then told the Delacours what had actually happened. They were shocked at learning about the killing curse bouncing off of Fleur. After discussion they accepted the Potter's belief that Harry's mother's protection had been passed on to the embryo, which shared her blood. They also agreed with the Potters subterfuge in not revealing what had actually happened. They then talked about what to do with Pettigrew and Voldemort. To stop Voldemort from leaving the transfigured body, they decided to cancel the transfiguration and dose him with Draught of the living death. The potion was quickly mixed and before the next morning, Voldemort's body was resting in the Delacour's cellar, hidden under a Fidelus charm.
When he awoke the following morning, Harry told Fleur "I am leaving Hogwarts, I will finish my education at Beauxbatons, or hire tutors. Every year at Hogwarts, I have had some near death experience. Now that I am going to be a father, I have to be more careful. Also, with idiots like Fudge and Dumbledore, I prefer not to have you living in England" Fleur looked at him, smiled and said "Thank you, that part of your life, Voldemort, the Dursleys and Dumbledore is over, now you can live the life your parents wanted you to have, when they gave their life to save yours"
As the years went by, Dumbledore could not understand how no trace of Voldemort was ever seen again. Harry completely ignored his requests for a meeting, and after using an eight year old in the tournament, Dumbledore had been banned from entering France, so he could not visit Harry.
His searching eventually turned up the ring horcrux and the fake locket, before he died from the curse on the ring. Of the few people who found the room of requirements, none realised what it could be used for, so the diadem was never found, Sirius in the meanwhile had followed Harry to France and never moved into Grimauld place. The Lestrange's eventually all died in prison, and the Goblins, upon seizing the vault, destroyed the cup as it was "tainted".
Harry meanwhile lived a happy life, and died an old man, with a smile on his face, never knowing of the prophecy, or that he was an horcrux.
As for Voldemort, he did not realise that although the horcruxes could stop you from passing on, they only stopped you from passing on before you reached a certain age. As the fidelus secret was passed on from Harry to his children, the passage of time caused Voldemort to die in the sleep induced by the Draught of Living Death.