In 1997, Lord Voldemort finally attained victory at the Battle of Hogwarts, where he defeated Harry Potter. Instead of merely killing him, he used a containment spell, where poor Harry could not escape, and worse, was under constant pain and disorientation. Even worse than that, he could not die, and thus, Voldemort could not die. He stormed Hogwarts, and awaiting he and his Death Eaters was the full fury of Dumbledores Army and the Order of the Phoenix. Despite being the most powerful wizard in history, the sheer rage and determination of those who ever cared about freedom from tyranny and evil, kept him at bay, and the Death Eaters were forced to flee. With no hope as Harry Potter was presumed dead, rebellion en masse against the powers that be began, and so started the Wizarding Civil War. Wizarding families began leaving the country in floods, as the war become unbearable to live under. The final stroke perhaps was the total destruction of Diagon Alley between 3 different fronts. The Weasleys were among those who left, and grief hung over every one of them as they retreated from Ottery St. Catchpole, their only ever home.
With an unshakable interest in muggle culture and especially in their technology, Arthur relocated his family to Gotham City in the United States, which aside from being a major port, financial center and media capital, was home to Wayne Enterprises, which was a technology boon. Arthur got a job in the WayneTech division, and managed to fool CEO William Earle and all the lower level suits that he was a physicist, as well as a research engineer. Obviously he knew very little about even the most basic muggle devices, but through a little magic and quick thinking, he managed to get his job done competently. Ginny convinced her parents that she need not finish her magical education despite the numerous magical schools and academies across the country., because she was a charter member and veteran of Dumbledores Army. Percy had decided not to rejoin his family, but he did leave the Ministry, eventually relocating to France where there was a low Death Eater population. He visits his family on birthdays and holidays.
Their official address was smack in the middle of Gotham, but the Weasleys actually lived in an abandoned mansion on the outskirts of the city, which is enchanted to make their presence undescribed to muggles. About a year after the Weasleys got settled in, Hagrid came along to join them. Hogwarts became filled with pureblood propaganda, the landscape became bleak and ugly, and most of the families that didn't or couldn't flee chose to home school their children instead of going to an awful place full of life. "How ironic, said Hagrid,"that a fella who believed in wizard superiority ended up destrying the whole country, that monstrous bastard." With a heavy heart, Hargrid moved to Gotham, building another ramshackle hut beside the mansion(By choice, for privacy reasons and also not to intrude), and he also took along Fang, Buckbeak, and a few other creatures to keep him company. His home and animal friends were also kept from muggle sight. Hagrid eventually put his half giant heritage and bulky frame to good work, as a warden at Arkham Asylum.
Hermione Granger also left Britain after Harrys seeming demise. She was in a state of shock, and nearly suffered an emotional collapse after she realized the weight of what happened. She went to Australia, hitch- apparating with misguided tourists as her magic was not strong enough to apparate so far a distance, and portkeys were could be tapped. When she found her parents, she undid the memory modification she performed on them and came clean with everything that had happened. She told them that it was too dangerous to go back home, and that they should warn everyone that they care about that doom was coming to Great Britain. She also said she wanted to spend half the time with them if it was still ok, and half the time with the Weasleys. She did this out of altruism and out of loyalty, but she also came to terms for her love for Ron. She received a message from Mr. Weasley that they were relocating to Gotham, and eventually Hermione found them and decided to live with them for awhile. Her and Ron began "officially" dating soon after. She also enrolled at Gotham University, where she of course was at the top of all her classes and had a double major in nanotechnology and medicine. She also continued to study magic on the side through whatever texts she could salvage(A number of Dumbledores Army remained in the area surrounding Hogwarts, including Neville, who is now an Order member, so she could get them smuggled to her). She became one of the most powerful witches of her generation, rivaling Dumbledore and even Voldemort in raw power.
In 2004, Ron and Hermione got married. In 2007 a mysterious muggle vigilante known as "Batman" became big news in Gotham, and rescued the city by an attack from terrorists, including the head of Arkham Asylum, Dr. Jonathan Crane. No one, not even the magical Weasleys , nor Hermioneor Hagrid could figure out who Batman was. Also, Bruce Wayne returned to Gotham after a seven year absence and regained control of his birthright, handing the CEO position to Lucius Fox. In 2008, an insane terrorist known as The Joker terrified the entire city, murdering officials, blowing up hospitals, and disfiguring, both physically and mentally, the high profile District Attorney Harvey Dent. Dents murder was eventually leaked out to be an act of self defense by Police Commissioner Jim Gordon to protect his family, in spite of a city wide manhunt against Batman who was accused of dents murder as well as several others.
Ron, for a short while, both out of emulation of Batman and out of a thirst for adventure, became a vigilante. He flew back home to England and recklessly caught a couple of random Death Eaters for the Order, and also attempted to root out The Joker in Gotham, but was convinced to back down by his family and also by Hermione, fearing for his life. Even magical folk were terrified of the mad Joker.
Pounding footsteps let him know he was coming. The door quickly opened, and the massive, bearded, Goliath like warden who called himself Rubeus Hagrid was standing there. He had a swagger in his stance and a sort of arrogance that he usually didn't have.
"Shut up your muggle face, you have a visitor."
"I have a feeling you aren't who you say you are."
Hagrid hocked up phlegm and spat on the Jokers face.
"Now I know you aren't who you say you are."
"SHUT YOUR FUCKING MUGGLE MOUTH! HE'LL BE HERE ANY SECOND!" Hagrids shout was so loud that it woke up several patients and caused a ruckus.
Soon the corridor gave way to a man wearing an emerald green cloak. Hagrid opened the door and let him inside the cell.
The man took off his cloak, and revealed himself to have a long white mane of hair, piercing eyes and the same air of utter condensation and arrogance that Hagrid had seemingly just acquired. He looked quite old, but there were no blemishes or tell tale signs, this suggests he must have had cosmetic surgery.
"Greetings Joker, do you have any idea who I am?"
"You are probably a low level henchman of the man who calls himself 'The Dark Lord'."
"What? How dare you insult the noble house of Black? Though a muggle like you would have no idea what that is anyway. And where do you get off calling the most powerful wizard in history in such rude terms?"
"I know a lot more than you think buddy. And Voldemorts really small potatoes. Before he won, Harry Potter defeated him at every turn, even when he was a baby. Batman would make mincemeat out of him."
Lucius held back a laugh. The Joker was clearly insane. Aside from his slurred speech pattern and sociopathic tendencies, the thought that a mere muggle, even a highly trained one, could defeat Voldemort or most wizards for that matter was laughable.
"Besides, the very fact that you are kidnapping me shows that Voldemort is weak. A sign of a decaying society is when a ruler hires mercenaries."
"You will help us, one way or another." Lucius and his son Draco, who was under the effects of polyjuice potion, both pointed their wands at him.
"You'll just have to imperio or posess me. Youre not talented enough to do possession, are you?" The Joker spoke in an almost demonic tone.
"GOOD IDEA. IMPERI…WHAT THE BLOODY HELL WAS THAT?!" Lucius' wand was sliced in half by something that fell on the floor, a blackpiece of alloy that was shaped like a bat.
Hagrid(really Draco) pointed and shouted "THERE HE IS!", but his wand was cut in half as well by another shooting batarang. A dark figure hanging from a high rail came crashing down, wearing a mouth mask and spraying some sort of mist.
Lucius and Draco attempted to flee, but were immediately knocked out by the sleeping potion. So was the Joker, but he had enough time to sarcastically shout his praise before being knocked out as well.
Batman stood over the two unconscious wizards, and he drew a needle from some recess of his. He injected the burly warden with some sort of serum made up by Lucius Fox to accelerate the effects of polyjuice potion. He soon shriveled into a blonde, lanky man in his late twenties or early thirties. He carried both captives out of the Jokers cell, locked the door, and exited out of the front with most of the patients watching him. Waiting outside was Lucius Fox, the CEO of Wayne Enterprises.
"Are you ready?", he asked with a smile
"Yes", said Batman in what Lucius thought was an annoyingly low register.
"Alright, then lets get these guys locked up." Batman held on to Lucius Malfoy and Draco Malfoy in his arms, held Foxes hand, and in the blink of an eye they disapparated out of the Narrows.