The messy haired young man appeared out of thin air with a soft pop in the middle of an alleyway just off one of the many of busy thoroughfares of King's Cross, London. He didn't need to worry about any curious eyes discovering his most sudden method of arrival courtesy of a notice-me-not charm that caused all but the most determined minds from perceiving the space he was in as occupied. Hanging confidently between two of the man's fingers was a long length of wood, the supple piece of ornately carved holly being his wand. A remarkable tool that distinguished the man as a member of a secret world that hid from the eyes of the world at large. For you see, this man was a wizard. Not just any wizard, though. There wasn't a witch or wizard in the British Isles that would fail to recognise Harry Potter.
With a cursory glance behind him down the deserted alleyway and a subtle flick of his wand to ensure that he was truly alone, he strolled casually to the mouth of the alley and looked across the road towards the impressive King's Cross Train Station. He could see the giant arches that supported the rather impressive glass roofing towering above the teeming populace. Muggles (non-magical peoples) swelled en-masse in a way that only an overcrowded metropolis can provide, moving in and out of the station in all different directions, faces blurring together in the crowd. To attempt to find anyone coming or going from the station would be an exercise in extreme concentration. Fortunately, Harry had other methods of finding those who didn't want to be noticed.
Softly leaning a shoulder into the nearest wall, Harry began to hum. It was a senseless tune that he was making up on the spot. Slowly he modulated the pitch up, and down. Up, and down over and over again. Unseen to others, his emerald green eyes began to take on a soft glow as his fingers started twitching his wand in tune with the beat. Few people could understand the magic that he was performing, for it was an old spell that had no incantation and wasn't found in modern spellbooks. It was a training exercise that old masters used to teach to their apprentices back before the turn of the millennium. He had learnt it from his mentor, who had learnt it from a very old wizard over a hundred years ago.
Essentially, Harry was creating a form of magical sonar. He was slowly and softly pushing his magic out across to the entrance of the station and when it encountered another magical creature or significantly enchanted magical item it would 'mark' it and show him what it had found. Satisfied, Harry dropped his tune and felt his magic pull back towards him and settle once more. Where before all he could see was a never-ending mass of indistinguishable faces, he could now see that there were a variety of magical persons moving both within the crowd and standing casually outside it. He smiled softly as a he saw small children that could only have been new muggleborn students (or aspiring students, in the case of a pair of 5-year-old twins who were jabbering away at their nervous looking older brother). There were quite a few of these families. Pureblood families would not have arrived at the station entrance, they'd have apparated their children as close to platform 9 and ¾ as possible. He watched these families carefully, observing the whole gamut of emotions from jubilance, to nervousness, to awkwardness as they slowly unloaded their children's school trunks. As he was turning his attention outwards, however, he felt a strong surge of pain rippling across his mind. It only lasted for a second, and it caught him completely unaware. Scanning the crowd once more he noticed a dreadful site. Sitting on the ground in the parking lot, surrounded by her school things and trying desperately not to break down into tears was a young girl with short black hair and round-framed spectacles, slowly rocking to and fro.
Harry was across the street and in the parking lot before he truly realised what he was doing, his only thought was to get to the little girl and do something for her, at least. Truthfully, he was scared. Not for himself, of course; but for the young girl. He remembered well his own circumstances. He remembered being dropped off in London in the middle of the night, and being told to never come back by his horrid relatives. He remembered being deathly afraid and alone. Being weak and vulnerable. And he remembered the kindly old man who had arrived in a pillar of fire to whisk him away to the magical world. While he didn't have a phoenix on hand to flash around on, he knew he had to do something.
He carefully pushed his way through the crowd, which was more difficult to do when you were charmed to not be noticed by others. He merely hoped everyone was too busy to worry about phantom pushes. He could feel the magic thickening in the air as he approached the young slip of a girl. He could see her with her face in her hands, slowly wracking with sobs. She was putting out a lot of accidental magic and it was only a matter of time before someone from the Accidental Magical Reversal Squad arrived to investigate. He had to calm her down before then, or things might become inconvenient for him.
He approached her slowly, his movements completely drowned out by the crowd. With a thought he dropped his own notice-me-not charm as he entered the sphere of her own magic. It was a weird approximation of a notice-me-not charm and muggle repelling ward. Fascinating, he idly wondered with a smirk. Accidental magic was rarely predictable, and was about as close as you could get to casting wards without drawing any runes. Alas, it was truly the domain of children, and he would rather cut off his wand arm than subject a child to the trauma required to produce its effects for study.
"Excuse me," he whispered softly in conjunction with a silencing charm, which muted the world outside of her little bubble. "Are you going to Hogwarts?" She jerked up suddenly, though he wasn't sure if it was due to the sudden decrease in noise level or the mention of the school. She looked up at him with wide eyes, confusion and terror warring within trying to process his sudden appearance.
"Who are you?" She half yelled, half cried as she gathered up her trunk and held it in front of her as a barrier between them. It was a bit shabby, with the material peeling off in several places and the lock looking like it couldn't keep out a half-determined toddler. Printed in neat letters along the top, however, was a name: Elisabeth Adley. "My parents!" She suddenly exclaimed, turning around in a circle and jerking her head around trying to find them. "No, no, no, no, no," she started muttering under her breath, her eyes growing fearful. "I'm sorry!" she cried out to nobody.
"Are you okay?" Harry continued softly, trying not to startle her again. "Are your parents here? There's no need to be sorry." Harry looked around but couldn't see any adults in an obvious state of distress. He needed to get Elisabeth to stop projecting her field so that her parents could find her. He turned to her once again and carefully, without showing it, cast a calming charm at the young girl. The effect was almost instantaneous, as he felt the accidental magic dissipate rapidly and the sounds of the crowd rushed back in to fill the void. Elisabeth was now looking at him again, this time with a little less apprehension. Making sure that he was kneeling to her level and that he had her attention, he tried again. "Hello, Elisabeth. My name is Harry Potter, and I'm a wizard, just like you're a witch." She flinched as if struck at the sound of wizard and witch which caused Harry to frown. "Are your parents here? Or do you need help getting onto the platform?" He offered with a smile.
"Hello Harry," she replied squeakily, looking at her shoes. "My parents…" as she looked up at him he was struck by a sudden fear that was not his own. He felt a hand grab the back of his robes and pull, lifting him clear off the ground for a split second before he came crashing down on the ground, cracking his head on the pavement. As pain blossomed in the back of his eyes he heard Elisabeth cry out in terror. He snapped his wand up, casting a new notice-me-not, to see that a man had now grabbed hold of Elisabeth's arm in a vice grip and was squeezing hard.
"No Daddy, please!" She cried out in pain. "I didn't mean to, please. Stop." She was struggling futilely against the hold, her arm turning red where the man's grip was unbroken.
"How dare you use your ungodly witchcraft on these good people! On me!" The man was seething, teeth clenched as tight as the grip on his daughter's arm. "It's bad enough that you've cast shame on our family in the eyes of God with your freakishness, but you spread your devil magic to others," he continued menacingly. "If we weren't casting you out of home to this cult of Satanists, it would be the belt again for sure," he smiled cruelly. He raised his hand, and Elisabeth began to struggle like a caged animal. Harry had seen enough. In a rage, he raised his wand and petrified the man in mid strike, then in a pique of inspiration performed a confundus charm as well.
"That, I think, is enough," he hissed sibilantly into the man's ear as he came around to view him from the front, quickly pulling Elisabeth from his grasp before sending the traumatised girl to sleep with a charm. Pulling more parseltongue into his speech, he coldly regarded the terrible excuse for a human being in front of him. As he stared into the man's eyes, he tore into his mind, laying bare his entire soul. Michael, the man was called, was looking at him in horror, believing him to be the devil himself, judging his very soul. Harry grinned maliciously, feeling no need to disabuse him of that notion. His eyes were glowing with power, and his voice penetrated deep into the father's mind. "So callously, you treat one of my own, with no regard for the forces that you contend with," Harry subtly conjured a large python which began to weave its way around the man's ankles, causing the man to nearly pass out in sheer terror. "Your disregard for one of my children has just cost you dearly Michael Adley," he intoned with as much force and gravitas as he could muster. "I'll be waiting," he boomed at the man before with a sharp crack, he and the snake both vanished, taking poor young Elisabeth them.
Michael Adley stood there, unmoving, in the middle of the crowded parking lot of King's Cross Station. The crowd continued to move along, and paid him no mind.