Author: Sparkle Itamashii

Title: Missing Persons

Notes: AU where Laura is Derek's younger sister, best friends with Stiles, and goes missing. Meant to go with the "Missing Persons - DerekStiles - Teen Wolf" Youtube video by Adrienne.

Prologue

High in the midnight sky hung a full, golden moon, bright pinpoints of light scattered thickly in the cloudless night. From the ground a pale mist had risen rolling over the forest floor, caressing the trees as it thickened, swirling up to the lowest of the branches. The air was still, almost stiflingly so, and the creatures that normally inhabited the nocturnal hours lay silent. All eyes tracked the darkened figure as it prowled the forest, passing them by without so much as a sideways glance.

It was on the hunt.

She had seen it before, had taken flight when she knew it was her blood the creature craved. It would not stop to ask her questions, would not let her explain that what it sought she did not have. All of that she had left behind, in safekeeping. She wouldn't tell him that, though, even if he would give her time. It was to protect the others that she fled now.

An eerie howl pierced the night and she paused long enough to listen to where it had originated. It was closer than before, following her trail, tracking her scent into the woods. She was not far from town, traveling away from where the beast had wrecked her car, caused her to swerve from the dirt path and into a tree. She touched a hand to her forehead and it came away bloody. Very bloody. She blinked, scrunching her eyes closed tightly for a moment before opening them again.

She had to keep going.

"Laura."

She stifled a scream, turned to see the man standing to her side. Relief flooded her at the sight of him, though her vision blurred and slanted. "Peter!" she exclaimed, surprised to see him. She caught the scent of him then, took a frightened step back as he smiled. He smelled of blood, of tire burn and engine grease; like her car wreck. He smelled like the beast that had been tracking her since she left Beacon Hills.

The wail of a siren began in the distance, heading in the direction of her car's crash site. She hadn't called the police, and there was no one traveling that road.

"I'm afraid, my dear, that you're going to have to come with me," Peter said softly.

Something inside of her trembled at the words, and she fought the instinct to give in to the stronger predator. He would chase her again if she ran, and perhaps he would not stop politely next time. But she was fast in her true form, faster perhaps than he was. If he let his guard down, she could buy a few precious seconds to turn.

"Where are we going?" she asked quietly, saw that he was pleased she sounded cooperative now that she had seen him.

"Home," he replied. "I believe you left something there that is... of interest."

She studied him for a moment, wondered how much he knew, how much he had heard as she sat beside him in the hospital, researching on her laptop, scribbling notes onto pads of paper. She wondered how he had kept his healing a secret from her. Finally she nodded, as if to acquiesce to his suggestion.

"Lead the way," she told him, taking a step forward. He smiled, and she could feel the satisfaction radiating from him; he believed she would follow him. She should follow him, should want what he wanted, what she could practically feel twisting inside of him, ready to snap.

Revenge.

He nodded once, and then turned away from her. In that instant, she shifted, teeth elongating, nails becoming claws, bones morphing so that she could run easily on all fours. Before he had so much as turned back around to see, she was sprinting away, back in the direction of her car. If she could just reach it, the police would be there, and Peter would not risk being discovered. He would not risk being seen in his true form yet, and he could not take her away from the police if she didn't want him to. They would protect her, at least long enough for her to escape, to keep moving.

The howl that chased upon her heels bled with unbridled rage.

Heart thundering, lungs burning, she sprinted, long strides eating ground beneath her. The crashing of his chase stuck in the mists, echoed until it sounded as if he was running all around her, breathing at her heels. She could see the lights ahead, smell the burnt rubber from her tires, the smell of fluids leaked from her engine.

She pulled up short, looking over her shoulder as she caught herself up alongside the thick trunk of a tree at the edge of the crash scene. The cops were huddled together discussing the lack of a body, the ambulance resting in wait nearby. She parted the branches keeping her from them even as she shifted, became human.

She took a breath to call out, but the words never left her lips as the blow from behind descended.

Chapter One

A cool breeze shifted through the bones of the ruined house before him, stirring up ash and memories alike. Above, the moon was a sliver in the sky, barely more than newborn, but he could see around him as well as any human on a full moon night. His pale blue eyes traced over the front of the house, undamaged by the fire that had ravaged it four years prior- it had not fared so well against time.

He'd been eighteen that summer, the night he'd lost his entire family. It wasn't bad luck. No broken wire to spark, no mishap of the stove, no accident. Someone had come to his home, trapped his family inside of it, and tried to burn it to the ground. He'd been with his sister at a late night movie, driven home to the screaming of sirens and the cold weight of fear in his belly that told him he would find exactly what was laying in wait for real.

Only one person had managed to survive the fire. Their uncle, Peter, had been visiting from out of town. He had been sleeping upstairs when the fire was started, wasn't trapped in the basement where the rest retreated. They drove him away from the scene in an ambulance, but not before Derek had seen the flaking, scorched skin down his uncle's face, caught the reek of burned flesh as it filled the night air.

Anger.

That was all the rest of that year held for him. Blind, unadulterated fury. He knew who had done it, or at least who had caused it to be done, but he didn't want to believe it. He had loved Kate, had told her secrets about his family that he had sworn to never tell another living soul. She had been so gentle with him, assured him that his secret would be safe with her, that she wouldn't tell.

She hadn't told, at least as far as his hunt for her had discovered- and he had hunted her, as soon as he realized what she had done, how she had betrayed him. How loving her had cost him his family. Put Peter in the hospital, possibly forever. Gave him and Laura nowhere else to turn, forcing them to take refuge with a small family of humans that were fond of Laura. He'd been unable to stand them, especially her best friend with the name he could never pronounce; a fact which sent the two of them into fits of laughter any time he tried.

He'd left before school could start again, before he had to make a decision about attending college. He'd left because Kate had left, because her family had learned what she did and sent her away to relatives. Not as a punishment, he knew. It was sanctuary. They knew what he was, perhaps had always known what he was, and they had moved her to protect her from him. He had been seeking her since then, had found himself only days too late the past three times.

And then the note.

Trapped beneath the blade of his car's wiper, fluttering like a frantic, caged bird. He had pried it from its resting place, unfolded it, scanned the precise lettering. He didn't recognize the scrawl at first, as it had been years since he'd see it.

Your sister would like to see you at home.

That was it. Nine words, no signature. It hadn't needed a signature or an explanation; the words were written in her blood, the paper stank of her fear.

So he found himself 'at home' as the letter indicated, but there was no sign of his uncle. No scent of family or wolf. Only the faint scent of charcoal and ash, the heavy weight of his past as it perched upon his shoulder, gazed out upon the house with him. The scent of Laura's blood was strong here, but not fresh. She had been here, or someone had brought her blood here, but it was days ago; the days it had taken him to get himself back to Beacon Hills.

The wind shifted and he caught scent of something else just then. It was earthy and sharp and fresh; something human. A vague sort of recognition tickled at the back of his mind, the sort he couldn't quite place. Someone was here, though, and they didn't belong. He pocketed his keys and began to move toward the house.

The light from the small electric lamp spilled over his shoulder, illuminating the pages and pages of tilted scrawl scattered around him. He sat with one knee pulled up to his chin, pen in hand, brow furrowed as he transcribed gibberish from a worn, well-read page onto a clean sheet. Three notebooks, bound with tight, metal spirals lay open to varying pages, dog ears at the edges of many, post it notes sticking out at all angles. The faint sound of music dripped from the buds nestled in his ears, accounting for the fact that he did not hear Derek's approach.

He grabbed at a loose sheet, caught sight of the dark shoes at the edge of the room, followed them up the legs, torso, chest... until he was staring a scowling Derek Hale in the eyes. "Oh," he said intelligently, grabbing at the lines of his earphones to remove them.

"Stilinski," Derek replied, dredging up the name from memory. This was the kid whose father had taken him and Laura in when their home had burned. The kid with whom Laura had stayed when Derek had left town.

"Stiles," the boy corrected absently, gathering the papers and notebooks forming a nest around him into some semblance of a transportable pile. "I'm sorry, I didn't realize- what are you doing here, Derek?"

One of Derek's dark eyebrows rose. "It's my house," he said, enunciating each word very deliberately. His head tilted just slightly. "I should be asking you that question."

"As to that..." Stiles responded, clacking the pile against the floor to straighten it before looking around the room with caution, as if expecting something might attack him.

"Yes?" Derek prompted.

"I was thinking," Stiles told him, unfolding his legs and clambering to his feet.

"About why you're here?" Derek asked impatiently.

Stiles gave him a strange look. "No, that's why I'm here," he said by way of explanation. "I came here to think."

Derek stared at the boy standing nervously before him, lips pursed, brow furrowed in a way that suggested he was trying to decide if he should kill him or let it go. "You drove all the way out to my burned out, abandoned home in the middle of the night on a school night... to think?"

"That sounds about as crazy as my life has become, yes," Stiles agreed, nodding slightly.

"And those?" Derek said, indicating the sheaf of papers encapsulated by the notebooks now.

"Ah..." Stiles looked down at the pages, eyes wide. His heartbeat skyrocketed in Derek's ears. "These? Definitely homework. Just homework."

"You're lying," Derek said, with such a matter-of-fact tone that Stiles knew he wasn't just guessing.

"You're right," Stiles said without elaboration. "And I should be sent home immediately."

Gathering his courage, he grabbed the lamp and attempted to scoot past the scowling man between him and the only exit. Derek grabbed his arm as he passed, grip tight enough to hurt and strong enough he couldn't keep pressing forward and break it. A strangled whimper escaped Stiles' throat and he halted, leaning backward to alleviate the tension between them a little. Derek, as nearly as Stiles could tell, growled at him.

"The last time I was in Beacon Hills, your father was the sheriff," he threatened, low in his throat. "Do I need to call him to tell him where I found his son trespassing, or are you going to tell me why you're really here?"

"I can't," Stiles blurted, then winced, looking around again. "Derek, I can't, he's-" He broke off the sentence, closing his eyes and hiking up his shoulders as if expecting a blow. When the only result of his outburst was a continued glare from Derek, he relaxed the slightest bit, dropped his voice to a very hushed whisper. "He's watching us, or he was, or he will be, but which-ever it is, I can't talk about anything with you here." He gave Derek a significant look, and the grip on his arm loosened a minute amount.

Raising his nose, Derek sniffed the air, found no trace of anyone but the two of them... except... he could smell Laura's blood, days old, and a fainter scent beneath it that he did not recognize. Whoever or whatever had put her blood on the door, and he could see it on the door now that he was looking, had not been back since.

"Trust me, we're alone," he told the human. "Now tell me what you're really doing here."

For a moment Stiles stared down at the papers grasped tightly in his hands, face tight as he weighed his options. Derek wasn't going to just let him walk away. But... he couldn't shake the feeling that he was being watched. That the guy who had pulled him from his jeep, slammed him against the side, and threatened his life was waiting just outside of his range of sight. He closed his eyes, trying to block out the words that had haunted him for the past week.

"I will rip her apart... your best friend."

He couldn't let that happen, and perhaps that meant trusting someone else.

"Have you... Laura never found you, did she."

Derek swallowed thickly. "No," he said. So Stiles knew, or at least had an idea that she was in trouble somehow. "She was looking?"

"Of course she was looking!" Stiles burst out angrily. "You disappeared and she only stayed here because she had to! You stuck her with us and you disappeared!"

Lips almost curled into a snarl, Derek pulled Stiles back until he could look him in the eyes. His pale eyes held the slightest tint of red Stiles couldn't have seen in the dark. "She wasn't old enough to come with me," he said sharply. "I left her in your care. She-"

"You didn't 'leave her in my care.'" Stiles interrupted angrily. "You didn't leave her in anyone's care. You just left."

Derek's jaw clenched shut, and his eyes closed. He looked as if Stiles had hit him physically, and for an instant Stiles regretted the jab just a little bit- until he remembered that if Derek had been here, Laura wouldn't have left to try to find him. She wouldn't have been picked up by someone Stiles hadn't recognized, someone obviously insane, someone who had ordered him to translate the gibberish in the notebooks or he would kill her.

The notebooks, Stiles thought with a sick feeling, that he'd had zero success translating on his own so far.

He sighed, held out the notebooks. Derek glanced between them and the human, and then accepted them with both hands. "What are these?"

"Honestly?" Stiles asked, scratching the bridge of his nose. "I wish I knew. Before Laura left, she gave them to me and she said that... if you came back before she did, that I had to give them to you. Last week, some guy assaulted me at the gas station, and told me he knew about the notebooks, and knew I'd been friends with Laura, and that he wanted translations of what was inside. He said..." Stiles hesitated when his voice caught on the words. He swallowed thickly. "He said he'd be watching me, and he said he'd kill her if I couldn't. And Derek..." Derek met his gaze, saw the hopelessness captured in Stiles' brown eyes. "I can't."

It was with great effort that Derek tore his gaze away from Stiles' and looked down upon the notebooks in his hands. He cracked open the top one, to where a sheaf of loose leaf paper was shoved. His pale eyes scanned the quantities of scrawl filling in the lines, what appeared to be an amalgamation of languages from around the world. Some of the loose pages were Stiles' attempts at translation; he had gotten some of the French, some of the Spanish, and a little of the German. None of the Latin, Gaelic, or Polish. Then, Derek's eyes narrowed in concern.

"Who's the third?"

"The third what?" Stiles asks, tipping his head slightly to see the upside down papers.

Derek obliged him, turning the notebooks so he could see the writing. "Handwriting," he said, drawing a finger over the three lines of blue ink at the center of the loose page. "I recognize Laura's. You've kept yours on separate sheets. So who's the third?"

Stiles snatched the paper from atop the notebook, put it closer to his face. The handwriting was so similar to Laura's he had never noticed a difference but... there, the loop of the e's were different, the small flair at the end of the m's and n's. It was obvious now that someone had pointed it out, and he cursed himself for not seeing it before. He'd been in such a panic, depriving himself of much-needed sleep trying to solve this alone.

"I don't know," he said absently, brows knit and eyes narrowed as he clawed at his memory like a hawk, trying to force it to give up the necessary information. Something, anything that would tell him who would have been writing with Laura. Who had she been friends with after the fire? He couldn't recall her talking to anyone that could have written in... whatever language the blue script was. She talked to him, and to his father, to his best friend Scott. He had seen her talking to Lydia, and to Scott's girlfriend, Allison on occasion, although they always seemed to be awkward at best. He knew that she sometimes went to the hospital to speak to her uncle, who was in a coma after the fire had nearly burned him to death.

After the fire, something within him pointed out.

But what about before?

There had been someone before the fire, and Stiles' eyes lit up with the memory. "Kate!" he exclaimed, smacking his forehead. "Your- Your girlfriend, right?Before she left. Before the... well, this," Stiles said, indicating the burned out building around them by waving the paper in his hand. "Your sister hung out with Kate a lot. She said they were working on a project- maybe this is it?"

Derek frowned, plucked the scribbles from Stiles' hands. "You're right, but that doesn't help us much," he said. "I can read what Laura wrote, with some time. But that's archaic Latin. It's an Argent language, one that whole family knows. They won't help."

"What if they would?" Stiles asked slowly, shoving the idea that Allison might be able to read archaic Latin of all languages to the back of his mind for now.

"What if... what if I could get them to help?"

Eyes narrowing, Derek took a step toward Stiles. "Get them to help how?"

Stiles swallowed thickly, suddenly afraid at the way Derek had him pinned beneath his gaze, how much larger the other guy seemed when angry. "My best friend Scott, do you remember him? He's dating Allison. Allison Argent, Kate's niece."

"No," Derek said sharply. "There could be stuff in these notes that they can't learn."

"Oh like what!" Stiles asked, oozing impatient sarcasm... and then his eyes narrowed thoughtfully. "You know what's on those pages. You already know."

"No," Derek said quickly, and began to flip through the pages until he found a series of drawings. "But I have a suspicion, and if it's what I think it is, then I'm in a lot of trouble and so is Laura. Here." He turned the notebook and set it into Stiles' palms. He traced a finger across the sketches.

"What is it?"

"It's an amulet. Well, the engraving on an amulet, anyway. It's mentioned a few times on the first pages I looked at."

"You can read that gibberish?" Stiles interrupted before Derek could go on. "There are at least 3 different languages. The words I translated are in no order, make no sense. Some of them aren't even real words."

Derek shook his head, waving a hand to dismiss the idea. "It's a system Laura and I worked out when we were kids," he said quickly. "The words are- look, it doesn't matter; I can read it, and I have seen this amulet before. Kate... Kate wore that amulet for years..." he trailed off, trying to remember for certain. His mind ghosted over the past, grasping at memories, and then his face grew dark, angry. "She... I never saw her wear it after she burned down our home."

Realization dawned on Stiles. "She did this?" he asked, gaze twitching up to indicate the burned out shell of the house around them.

"Yeah." Derek refused to look around, dropping his gaze to the floor instead.

Distracted for a moment, Stiles felt bad for the guy. He'd been young, barely 18, when the house fire had claimed his entire family. His mother, father, two of his younger siblings. His aunt, uncle, and their three little kids had been visiting, and only their uncle had escaped death. He could understand

"That's why I left," Derek said quietly. "To find her."

"So you were, what, hunting her down?" Stiles joked.

"I didn't catch her," Derek replied defensively, and it took Stiles a moment to realize he was serious. The look in the older boy's eyes told him just how serious, and something inside of Stiles shrank away from the heavy weight of revenge shining in Derek's pale eyes. Stiles was not a vengeful person, but he could understand why Derek would crave it.

"But you wanted to," Stiles said softly. "You would have, eventually."

"Yes," Derek said plainly. "And I would have killed her, and it would have been none of your business."

"Unfortunately, it's my business now," Stiles told him, indicating the notebook in his hands. "So she wore an amulet, and these notes are about it. So what is it? Worth a lot of money? Some kind of... powerful magical talisman?" He grinned at the joke.

Yet, Derek nodded. "The latter," he said calmly, reaching over and relieving Stiles of the notebooks. "She didn't tell me much about it, just that she believed it had the power to turn me into a human. She didn't take it well when I said no. What?" This last because Stiles was staring at him as though he had sprouted a second head.

"I'm sorry," Stiles apologized insincerely. "I was under the impression you were sane and that I was going to get some serious help here."

For a moment, Derek just stared at Stiles, trying to puzzle out what the boy was trying to say. His eyes flickered back and forth between Stiles' eyes, searching for some sign that the youth was joking, but he was dead serious. He didn't believe Derek and that meant- "She never told you."

Both of Stiles' eyebrows hiked in question. "Who never told me what?"

"You were her best friend for how many years? She lived with you for what, four years?" Derek asked skeptically.

"Three," Stiles said, irritated when he realized Derek was talking about Laura. "She left a year ago to find you."

"Ok, three," Derek conceded, ignoring the jab in order to continue being flabbergasted by the boy's ignorance. "And she never told you."

"Told me what?" Stiles asked, exasperated.

"That she's a werewolf," Derek said, as if it were the simplest fact in the world.

"Oh, thaaaat!" Stiles said sarcastically, but his eyes widened when he realized Derek was glowering at him. He was serious. "Oh my god, you really believe your sister is a- Holy god what the hell!"

This last because right in front of him Derek's eyes flashed red, his face morphed, and he was pinning Stiles to the doorframe beside them with an unearthly snarl. Briefly Stiles considered squirming, but the strength of the press of Derek's clawed arm across his chest told him it would be useless. He stared into Derek's formerly pale grey-green eyes, now a bold red, feral, and wondered how his life had gotten to this point.

"Were. Wolf." Derek said slowly, around a mouthful of needle-sharp fangs. "The Argents are a family of werewolf hunters and if they've taken her then I don't have time - Laura doesn't have time - to mess around getting you to believe. Are you going to help me or not?"

Stiles swallowed thickly, because he knew that 'or not' probably meant he would be buried somewhere in these woods where no one would ever find him. He tried desperately to wrap his mind around what just happened, and managed a weak nod. "Ok, yes, ok, god. You're a werewolf, Laura is a werewolf. Magical pendant- I get it. I'll help."

Derek glowered at him, inches from his face, for a moment longer, and then released him, backing up a step. His face smoothed, his eyes paled and then changed color, back to their former grey-green. Stiles rubbed his chest, and stared hard. Werewolves. It made a certain amount of sense- or at least, it made certain other things in his life over the years make sense. There was no sense in werewolves.

"So what else should I be aware of before we go on?" he asked, a weak attempt to joke at best. He could feel himself shaking. "Vampires? Faeries? Lochness monster?"

A muscle in Derek's jaw twitched. "I never saw Kate wear the amulet after the fire," he said, picking up the earlier thread of conversation instead of hitting Stiles. "I don't think she took it with her."

"She didn't," Stiles said, so matter-of-factly that Derek calmed a little. "She gave it to Allison," he explained. "I've only seen her wear it once. I think it's just jewelry to her, and not very nice jewelry really. I think she said Kate gave it to her for her birthday the year she left."

The both sat quietly for a moment, turning over the information. Derek shifted uncomfortably. "I find it difficult to believe she would leave something so... arcanely valuable in the hands of a... a what, fifteen, sixteen year old?"

Stiles shrugged. "Some people leave things even more valuable in the hands of fourteen year olds."

Derek sighed heavily, couldn't meet Stiles' eyes. After a time, Derek straightened. "You said you were assaulted," he remembered. "You didn't recognize the guy? It wasn't one of the Argents? Allison's father?"

Shaking his head, Stiles winced. "I- I dunno. He was little taller than me. Blue eyes. Clean shaven. Blondish-brown hair." He managed not to chuckle at his next thought. "Good cheekbones, like yours."

Scowling, Derek smacked him upside the head with the notebooks and turned to leave. "Where's your car?"

"Oh my god, please don't hurt my car!" Stiles yelped, running after him. The patina of calm over Derek's emotions was only just barely enough to keep Stiles from further harm as he rolled his eyes.

"I'm not going to hurt your car," he assured the youth as he prowled out the front door, down the steps, toward Stiles' Jeep. "You said he assaulted you at a gas station. I assume you had your car. I should be able to pick up his scent."

"You can- nevermind. Whatever," Stiles said quickly. He watched as Derek practically ripped open his door, sniffed around it, closed his eyes to focus. It made Stiles uncomfortable, like at any moment he expected Derek to turn into a full on wolf and attack him again, or at least attack his vehicle.

Suddenly, Derek's eyes widened, and he turned to look at Stiles as if the boy had been hiding information. "Is my uncle still boarded at the hospital?"

Stiles pursed his lips before answering. "No," he admitted. "Shortly before Laura left, your uncle disappeared. She said maybe he went home, like maybe he was too sad here after he lost his family. The hospital wouldn't tell us anything, and my dad wouldn't investigate it. Why, do you think they took him too?"

Derek's face was grim. "No, I don't think he got taken... I think he took her. I think he assaulted you." He raised his nose to the wind, tried to catch the faint scent beneath the blood that he had caught earlier. There it was, the same scent, though barely, just barely there. He would not have recognized it without the fresher scent from Stiles' car.

"So, what?" Stiles asked, trying to make sense of the declaration. "He took her to figure out about the amulet? Why didn't he just ask her? She would have told him."

"I don't know," Derek said grimly, shutting Stiles' door and moving around the Jeep to get to his own car. "But I'm going to find out. I'm going to get her back. You're going to help me."

"Sure," Stiles agreed again. "Of course." He held up the few pieces of paper Derek was leaving with him, the pages with archaic Latin scrawled between the lines. "I'll get these translated."

Derek nodded, ducked into his car, and left Stiles standing alone on the front porch. For a moment Stiles stood there, fingers crumpling into the sheets in his hands, watching the pitch camero disappear. Then his eyes shifted slightly, to another pair of red lights, perfectly still in the distance. He shivered, the hairs on his neck and arms rising as the fear that had haunted him the past week began to claw at his belly once more.

The crimson eyes blinked once, returning his observation, and then vanished into the night.