Once upon a time, in a far-away land, a young prince lived in a shining castle...

Adrien Agreste was not a prince by blood, or title. His family was noble and wealthy, but not enough to be in a position of high power or prestige. Despite this, the servants still affectionately referred to him as "prince," if at least for his kindness, honor, and appearance.

And true, he would object to this, but he knew it was all in good fun. He wasn't like his father, after all, he did have a sense of humor.

He could not remember a time when his life wasn't bright or shining. He'd always had whatever his heart desired, made fast friends with the children of the staff, and though he didn't exactly like studies, he still excelled in that subject as well. His father was distant, true, but his mother (who more than made up for it) assured him since he was small that it was because he had some...extra duties to tend to. It was nothing personal, nor did it mean he didn't love his family. And on the rare day when his father could leave business behind to see his son, he proved her right.

Words of encouragement, fatherly embraces were rare, but no less genuine. Adrien treasured every one of them.

He never had the chance to learn just what his father's extra duties were, exactly, although...

When he was ten years old, he stumbled upon his father speaking to a foreign man one afternoon. The two men had been speaking in hushed voices, his father's face was a heavy mask of concern, but both fell silent when they noticed the young boy. Adrien only had a chance to see a black box being held between the two men before his father collected himself and told him to go back to his room. Now.

Both the box and his father's troubled expression weighed heavily on his mind, but he did not know how to broach the subject. And the foreign man wasn't seen at all after that. Adrien watched the door, but he did not appear, nor did any of the servants know a visitor had even come. It was as if he'd never been there at all.

Mere days afterward, a terrible sickness hit the mansion.

...and nowhere else.

People who had been the picture of health one day would be so weak and feverish they couldn't even leave their bed the next. And then in the days following... Well, they preferred not to think about it too long, and try instead to focus on saving who they still could. Every day the mansion got a little quieter, felt much emptier. All at once, the brightness of their lives had vanished.

When Adrien's mother was stricken with it, the physician advised that Adrien and the other children be sent away, for their own health and safety. Thus the boy found himself being helped into a carriage bound for the next town, with a small handful of others his own age – the children and younger siblings of some of the other staff.

"It will only be for a few weeks," his father promised. "At the most. Until we're sure this has passed and it is safe for you to return. You'll be staying in the summer mansion; it's further away from the pollution of the city, you'll be safer there." He clasped his son's hand briefly, and then the carriages were off.

He hadn't known at the time, but that would be the last time Adrien saw either his father, or his home.

Despite the unfortunate circumstances of their leaving, he and some of his friends, particularly Nino, the only son of one of his father's favorite musicians, tried to make the best of their new surroundings. The summer mansion was smaller, so it did not feel quite as empty despite the smaller group living there. It was surrounded by a thick forest that provided cool shade and allowed dappled sunlight to decorate the lawns. One of the other boys found a river where they tried fishing or wading. The tutors were all still in the winter mansion, thus no one had lessons to attend. In spite of the direness of their situation, the group almost felt like they were on a vacation.

Adrien didn't even seem to mind the lack of news from his family. They had only been out here for a week, and there might not be much to report.

Two weeks after he left home, everything changed, very suddenly.

Late one night, when Adrien was supposed to be asleep, there was a heavy knocking at the door, one that seemed to reverberate in his bones. It made him uneasy, but he couldn't not answer it. He reasoned everyone else must be asleep because of the late hour, and since he was awake he might as well be the one to answer. So he did.

The visitor was tall and imposing, and Adrien couldn't help feel a bit frightened at the sight of him. Maybe it was his dark clothes, or the way he smiled with too many teeth. It might have been meant to look kind, might, but something about it was off. He wasn't sure just what, at first, but then he realized.

There was an air of magic around the visitor.

"Can I help you?" he asked, willing himself to sound braver, more grown-up.

"You are an Agreste, are you not?" the visitor asked, the fingers of his left hand tapping on his walking stick.

"Yes."

"Then perhaps you can help me. You see, your family is in possession of a certain...item of mine. It is of great magic and power, and I am here to take it back."

Adrien did not know of any such item, especially one that would be in his family's possession, and said as much.

The man only chuckled darkly. "Do not play the fool with me. I know your family has it, and it would behoove you to hand it over to me immediately. I am not afraid to take drastic measures." Those last words came in a terrible hiss.

"We don't!" Adrien protested, voice raised in desperation, annoyance, and a bit of fear. "Even if we had something that belonged to you, I wouldn't have it, my-"

"I have already seen to your parents." There was an undertone of something when he spoke those words that made Adrien's blood run cold. "I searched thoroughly. It wasn't there."

Adrien could only stare, the man's words rolling around in his head. "I have already seen to your parents." It probably shouldn't have been so terrible-sounding, but it was. Things began to click together in his mind; the aura of magic, the sickness, the lack of letters, he'd seen his parents... "What did you do to my parents?" he asked, his voice only wavering slightly.

"The ring, young Agreste."

"What did you do?!"

He felt something shift in the air. The visitor had a horrible expression of rage, the smile gone but still all teeth. "So you won't cooperate...Well, boy, I have my methods to make sure you do as I ask." The staff lifted, pointed straight at him. "Creating that sickness might have drained most of my current power, but I can do this much at least. And," he added, that cruel smile back. "This might be more entertaining."

All at once Adrien felt something shift. He felt heavier, unbalanced, and he pitched forward to the floor. The child cried out, but it sounded more like a yowl than anything else. He could feel muscles changing, bones shifting or elongating, his skin felt horribly itchy and hot. When he opened his eyes, he found he could see far better than he had a minute ago – but it was still dark, how could that be? He looked up at the stranger, lifted a hand – paw – towards him pleadingly-

The man just watched him. "Will you return my property, or do you want to be like this for longer?"

"I don't-!" Adrien began. He stopped, not at the sound of his voice – mercifully, that had mostly gone unchanged – but at how foreign it felt to move his mouth now. And how, when he moved his tongue to pronounce the words, it brushed against sharper teeth.

"Very well, then. Stay this way until you're ready to talk. Oh, don't worry, I won't just be sitting idly by, doing nothing," the man said. "I'm sure your family has hidden it somewhere, so I will be looking for it...Just know that you will make things so much easier for yourself and your friends if you confess first."

"What are you talking about?" Adrien pleaded. "I don't know anything!"

"Whenever you're ready to give up the charade, my boy. I'm patient." There was a heavy sound of multiple, tiny wings flapping, and the man vanished in a cloud of butterflies. With him no longer blocking the open door, a rectangle of moonlight was able to stretch into the room and fall upon the monster left behind.

Adrien Agreste did the one thing one could do when they were ten years old and just realized they had lost their family and had been transfigured for reasons they didn't understand.

He curled into a black ball and cried.

In the doorway, two small creatures hovered, looks of regret on their faces. They'd been too late.

Author's Note: So obviously, I'm not the first person in the fandom to get this idea. But I did want to try my own spin on it! This will be taking some elements from the Disney movie, but it's not going to be a straight copy-paste of the Disney script with the names swapped out, I can promise you that. I'll be adding my own spins on things as well.

And yeah, currently at this point it really looks like Hawkmoth is Gabriel, but hey, this is an AU. You can get away with a lot in AU. You could make an AU where Chat Noir is pink, and nobody can say boo about it because it's AU!
Disclaimer: I will not be making Chat Noir pink.