This idea is routed in the usual Harry is betrayed after Sirius death and leaves Britain trope. As usual he gets a letter from his so called friends declareing him dangerous and as usual he manages to escape Britain with insert girl here (this time Katie Bell). Of course not without leaving a decleration of exactly why he is leaveing as an open letter to the prophet. And as usual Dumbledore (dumb as such a master manipulators has to be) sends some of the people who have offended him the most to get him to come back. But hasn't Harry maybe overlooked something while acting rash and leashing out at those who offended him? Well lets find out.
Trust works both ways.
Harry was on his way home from work. Not that he had to work given that he took his inheritance with him when he fled Britain. But neither he nor his wife were the types to sit idle at home so both of them finished their (non-magical) education and found jobs that gave them a sense of being needed. Katie became a schoolteacher and Harry a social worker working with the child protective services of his new chosen home country. Their family would even grow soon, leaving all those traitors behind was the best thing he had ever done.
He arrived at the driveway of his house when he felt something was wrong. The wards were breached! Quickly he checked his concealed arms (pistols and wand) and carefully entered his home. Inside he saw them. The ones he once called friends and one of them was holding his wife hostage. He leveled his wand at the man who was holding a wand at his wives throat.
"I give you 5 seconds beast to release my wife or you die."
"Come on mate you won't hurt Remus. You also wouldn't endanger the girl like that. Just come with us, Britain really needs you!" said Ron.
"I don't give a fu** about that. You made it clear in your letter that you don't want me around so deal with it." replied Harry while carefully adjusting his position.
"No more moving Harry. Drop the wand or your wife pays the price!" shouted Remus and emphasized by strengthening his grab on her while his wand-tip began to glow "NOW!".
He dropped his wand raised his hands and took a step backwards. After this the beast relaxed a bit and reduced the pressure on Katie. Katie and Harry made eye contact one nod from both and they began to move. Katie managed to kick Remus on the foot and punch her elbow into him while this would not do much to the werewolf it still took him by surprise and she was able to duck just before Harry drew one of his guns and leveled three shots in Lupin's head. Katie grasped her wand from the body and opened up ad Ginny while Harry leveled his gun at Ron.
"Surrender or die like the beast."
Both Weasley's and Kingsley were shocked but all surrendered their wands. Katie gave Harry his wand back and both of them conjured silver daggers and banished them into the bloody mess that once was Remus Lupin.
"That is murder Harry. Will you slaughter us all?" shouted Kingsley
"That was a message. No one is allowed to threaten my wife like that. If he wasn't a werewolf he would have died from the bullets in normal self-defense." Harry replied.
"But he wasn't dead and would have recovered and wasn't a threat anymore. So that qualifies as murder. Go ahead and call the Aurors we'll confess to breaking and entering but you'll face the consequences for this. Or come with us and we'll find a way for pardoning you, if you do your duty in fighting You Know who." argued Kingsley.
Harry couldn't help himself he snorted and looked at Kingsley with a bemused look.
"A werewolf invading my home, threatening my pregnant wife and you think there will be any consequences, for what I have done to him? They probably congratulate me and give me a reward for putting down one of the uncontrolled beasts."
"You have changed. There were times you wouldn't have been such a bigot." said Ginny sounding disappointed.
"Oh poor GinGin disappointed in her knight? I wonder why you made very clear in the letter that you thought I was dangerous so why do you wonder now? I have nothing against werewolves in general only against those of them who invade my home and threaten my family." Harry snarled.
All invaders were quickly armed and bound. He looked at his wife. "Guard them please I check, if there are others around. This party is clearly missing Loony, the know-it-all and the squib." He ignored the silenced captives and searched the grounds but found no other intruders.
"Well it seems we are clear dear. Everything ok with you."
"Yes Harry, but I think I need a lie down. You can handle the rubbish for yourself right? Oh and don't expect the other three Ron says they refused to join this little exercise." His wife told him.
Harry forced the three of them to strip casted several spells to make sure they had no concealed stashes or other means to call for help and such and dumped them a night on a parking lot. After some time they managed to report back to Dumbledore who was shocked how such a simple mission could result in such violence. Before he could even send someone to check, if the potters had moved he was informed that one European country after the others closed their borders to magical Britain stating that they would not tolerate them sending assassination or abduction teams to them. The minister of magic was furious and with all borders closed the war escalated and threatened to reveal magic to the muggles.
Now it was no longer a question of being asked the ICW had seen this coming and was prepared they invaded Britain with a well prepared task force. Equipped with newly invented spells and revolutionary gear from the research team of someone who was only known as Agent Q (many members of old magical families never understood why this letter was that amusing for their co-workers) they had no problem dealing with the Death Eaters. Most prominent were ward stones that prohibited all magical travel in a large area. Once installed only special password protected port keys could be used as magic method of travel in that area they simply brought enough to cover all Britain. Their war-wizards were equipped with protective gear that was charged with runic shield pattern which allowed them to use their wand purely for offensive. It was also a shock for the Death Eaters when attacking them with Killing Curses triggered a special response of transfiguring a huge block of the air in flight path of the curse into some kind of gel rendering the curses harmless. Additionally they had a repertoire of spells that had the same ability of the Killing Curse and just passed normal shield charms.
Ultimately Voldemort couldn't escape the enemy troops anymore. For him the war-wizards had special orders and stunned him with a barrage of special stunners that could not be broken with a simple envenrate but needed a special counter spell known only to very few. The captured Dark Lord was transported into a special secure ICW facility and put on a drip with the draught of living death. Researchers did run several scans and experiments and found out about his horcruxes. After some time they developed a method to locate them and special teams were send to collect them. With some minor problems and unhappy goblins they got them all but one who was triangulated to be in Spain.
"Good morning Mr Potter I'm terribly sorry but we have an warrant to search your home from both the ICW and the Iberian Magical Government. Here is my Auror identification and here the warrant, if you have any questions or grievances please contact the due authorities."
Harry had little choice but to let the Aurors in. All they did was walking from room to room and looking at some devices. He became seriously concerned when the groups all started to enter the room he was in one after the other. One of them hold the device at him and began to move it up and down. Then the woman commented.
"Well that is unexpected. There was another living one, but that was a snake. We really need another option to get rid of the problem this time."
Harry and Katie were confused but promised explanations at a later date. Some of the Auros left others stayed to guard them. Some hours later both of them were invited to the Iberian Ministry. In a secure room a small group of people started to explain the problem to them.
"So in order for Voldemort to truly die this soulpiece of him has to be destroyed and the only way you know of is to kill him?" Katie was practically screaming and standing protectively before her husband wand drawn. "I wont let you! I thought you were different. She then looked at one of the ministry officials the pair knew well. "You promised!" she accused him.
"You misunderstand Mrs. Potter. We have no intention to harm Mr. Potter. Tom Marvelo Riddle is currently imprisoned in a controlled coma and can be kept such indefinitely. So he can easily disposed of once your husband perished naturally, may that day be in the far future."
Both Potter signed in relief.
"We would like however to study the phenomena. One of our best researchers Agent Q might be able to derive knowledge from you special situation, if we are allowed to scan you a few time. Nothing harmful or otherwise problematic. Each procedure would be explained to you and only carried through with your expressed acceptance. "
They did not agree instantly. But some time later both agreed to help the effort to understand this magic better so that it can be fought more effective. But no solution was found. Time was moving on and from time to time the Potters received much more welcome visitors from good old Britain.
"Hey kids Grandma and Grandpa are here."
Dan and Emma Granger hugged their surrogate son. He was ready to forgive Hermione only little time after the incident. He realized that he too had made bad choices in before and she truly earned a second chance after all the other stuff she helped him with. So he contacted Dan and Emma and heard that Hermione opted for not returning to Hogwarts after the fallout of him leaving Britain behind. She already was taking University courses during Hogwarts and was now attending fulltime. He invited the Grangers to holiday with him but urged the adults to keep him as a surprise.
The surprise ended in a disaster! When Dan and Emma learned of the letter they demanded for her to apologize. Hermione refused and her parents let her know that she would not be welcome at home for some time. She should at least stand with her mistakes and live up to them! With four people throwing accusations at her Hermione aparated out and was never seen again. Happy that the Grangers stood by them the Potters were delighted to grow closer to them. All assumed that Hermione would come back once her steam has run out.
"Hey James and Grace how are you two cuties. Oh hello to you to Harry." Said Emma smiling while giving out hugs and kisses to the little ones. Dan followed right behind. The Grangers were big believers in spoiling grandchildren. So a visit from them was always a big treat for his kids.
Sometime later while the kids were sleeping peacefully the adults were sitting on the veranda an talking.
"So mum, dad I thought about showing the kids a proper Christmas this year. We'll be taking a vacation back home now that everything is settled and safe again."
Emma could see that there were other reasons and decided to investigate.
"Harry I can see that there is more. If you need our support for something back home just ask."
"Well you know I go to a counselor for several years now. And that made me realizing that some of the grudges I held for a long time aren't really healthy. I let them go for some time now but my counselor and I agree that it might be a good idea to clear the air with some of them. Not Ginny and Ron their attempt of kidnaping is to close and they were already adults back then. But Luna and Neville were just scared kids. Maybe we can even find Hermione I know that you are hurting that she left."
Dan and Emma both had shimmering eyes at the thought of their lost daughter.
"Don't do this just for us. It is not your fault all you wanted was repairing your friendship. It was our stupid ultimatum and our daughters stubbornness to give in and see her error."
"It's not just you I also want to know she is doing. And I want her to know that she is forgiven even, if she can't live up to what she has done. We'll never be close friends after this but she is your daughter and she should come back to the family."
So the Potters found themselves in Britain at Christmas. From the Grangers home they toured the Isle with their children and had a jolly good time. Between the holydays Harry found himself at the entrance of Longbottom Manor. Neville greeted him and let him in. Harry met his wife Hannah and their three children. They talked about the time after Harry left Britain and how it affected everyone
"Don't worry too much. Most could easily see that Luna and I were just scared kids. We weren't your closest friends to begin with and we both come from respectable pureblood families. So mostly we were left alone. The Weasleys got hit harder Ron being your best mate and Ginny was slandered how she could supposedly love you and treat you like that. But the Weasley family also has many connections to other magical families so ultimately it ebbed away. Hermione was hit the hardest after what was written about her and after the hate mail I can understand her leaving Hogwarts. Wonder how Ginny and Ron convinced her to sign the letter she was quite furious at them and refused when we had gone to her home. She still was on her potion regime back then and not really well or else she would have hit Ron I think."
Harry looked at Neville with shock in his eyes. He had just taken for granted that the letter was genuine. He had never asked her, never tried to check if her signature was genuine. He cut his visit as short as he could without being impolite and rushed home. First he reexamined the argument with when he invited the Grangers to Spain for the first time. This time actually listening to what Hermione said.
"I did no such thing! …I'm a traitor? Big words from someone stabbing me in the back …I refuse to apologize for something I haven't done … Mum, Dad do you really take his word over mine? …" And then just before she aparated out he saw it in her look. While looking at her parents in a final plea to believe her and stay with her parents, despair then defeat.
He couldn't calm down now he rushed to Diagon Alley and after some time he managed to buy a book that contained several spells to spot out forgeries. He used one of them at the letter that started it all. Four names glowed green but Hermione's glowed red.
Harry didn't know how to describe what he felt in this moment, shame, regret, some of it was an old acquaintance self-loathing but this time he was sure he wouldn't be told that it wasn't his fault. Yes someone else forged the signature but he accepted it without a second thought. He was ready to believe his most loyal friend had betrayed him on the basis of something so easily forged. He did not investigate it all he even vilified her in his open letter to the prophet. He had taken away her parents! After watching the argument again with open eyes he realized that he didn't gave her any chance. The only outcome he was ready to accept back then was her growling begging for forgiveness.
He left his thoughts and realized he was crying. There was only one course of action left:
He had to find her.
So I end it here. Just imagine your self how it works out further. My picture of how esspecially Hermione (who did not sit in her little flat in despair for years upon years just waiting for Harry to come for her) would react wouldn't be recived well by those who belive in "Harry can do no wrong".
So if you belong to that fraction stop reading now. I'll give a little description on the main points I pictured had this story been longer.
We would have learned that Hermione is Q leads a research facility that she founded and is sucessfull in the muggle world too. I might have included Katie telling Harry it would be OK for her, if he was to marry Hermione and make her Lady Black (two houses two wifes blabla) before he goes to find her. She always knew his love for her was deep and now that she is aquitted it will sure be back and Hermione after some initial resistance will of course fall for him. Naturally that would not work, if Hermione either never had a romantic interest or she moved on and his now happily married with 2-3 kids. She would be OK with her parents being informed about her whereabouts but not giving them a freepass on forgivness (I loath stories were the Grangers take Harry's side over their daughters just like that and literaly tell her she is a bad person after they knew Harry for littel to no time) and tells Harry just to go back to his live.