A/N: Hey everyone! I know I haven't posted a lot lately, but I actually have been writing, I promise. This is my piece for the ML Big Bang, originally posted on AO3, with accompanying artwork done by the fabulous ladydelahautematigny on tumblr. You can view it under the tag "mbb2k17" on her blog.

The crime scene itself was rather ordinary, perhaps even disappointingly so, for after listening to Alya's giddy chattering about the case for a quarter of an hour beforehand, Adrien had been expecting something quite different. But there were no cryptic messages here, nor mysterious unidentified artifacts, nor anything even faintly risqué to be seen. There was only poor M. Kubdel, slumped over dead at his desk, and other than that not a single paper out of place.

Alya, naturally, had arrived at the museum well before Adrien, and had somehow managed to bully the officers on duty into letting her onto the scene. The two policemen were now standing guard at the doorway and looking thoroughly brow-beaten, as indeed most people did after confrontations with Alya. When Adrien had approached the scene, they both sighed heavily and grumbled amongst themselves, but neither made any effort to stop him from entering Kubdel's office. Adrien, who was nothing if not unfailingly polite, tipped his hat at the pair as he passed by and offered them a sympathetic smile. He had been on the receiving end of Alya's bombastic wit before, and the sympathy was genuine.

Alya herself was wandering slowly about the office, shuffling lazily through Kubdel's many assorted books and documents, occasionally pausing to read a page or hold a sheet up near the light, as though to check for a secret message penned in invisible ink. When she saw Adrien, her face brightened considerably, and she waved him over to her side.

"Alya," began Adrien cautiously, "what on Earth are we doing here?"

"Why, investigating, of course!" said Alya, as though it were perfectly obvious.

Adrien took another glance around the room. It was still a very ordinary-looking office. Along the walls were several oaken bookcases, with their shelves sagging under the weight of double-stacked leather tomes. M. Kubdel's desk near the center of the room was an old, battered thing, and covered with carefully piled documents and paperweights. In one corner was a stack of crates, no doubt containing artifacts from the museum, all of them undisturbed and labeled carefully in a neat hand.

His eyes settled once more on the dead Egyptologist, and he sighed heavily.

"I spoke with Nino before I came over," said Adrien. He turned his attention back to Alya. "He says that it's likely natural causes. No evidence of foul play."

Alya scowled at the mention of Nino. She and Nino had been together for several years, and though they were not wed, except perhaps in the commonest sense, Adrien had rather begun to think of them as M. and Mme Césaire. They could certainly bicker like an old married couple, in any case, and nothing could start them arguing quite so fast as a disagreement about work.

"Kubdel's daughter doesn't think that," Alya eventually said, without mentioning Nino. Very casually, she began thoughtfully rummaging through the clutter on Kubdel's desk, careful not to disturb the body. After she had exhausted her search on the top of his desk, she began to even more carefully check the drawers.

"His daughter is upset," countered Adrien, "and understandably so. But there's no evidence of foul play, Alya, and what in God's name are you doing?"

She had carefully peeled back one of Kubdel's eyelids, and was examining his revealed eyeball quite intently.

"I'm checking for signs that he's been poisoned," Alya explained patiently. She was not at all perturbed by Adrien's clear disapproval.

"Isn't that best left to the medical examiner?" he asked.

"Well," said Alya, releasing her hold on Kubdel's eyelid and straightening slowly, "I might feel more comfortable leaving it to the medical examiner if the police hadn't already decided that they weren't going to bother investigating!"

Adrien huffed at that, yet he could not deny Alya's point. Alya, sensing that Adrien was conceding defeat, sounded much more cheerful when she asked, "So, what do you think? The mysterious Ladybug strikes again?"

"The Ladybug?" Adrien asked.

Alya cocked one brow at him. She did not answer him right away, instead turning back towards Kubdel's desk. She slowly lifted a half-full teacup from M. Kubdel's desk, brought it up to her face as though she was considering taking a sip, and sniffed at its contents. She contemplated the scent thoughtfully for a moment, before setting the cup back down again. Only then did she finally respond to Adrien.

"You haven't been reading my articles," she said.

That was true. Between his work and preparations for the upcoming Christmas holiday, Adrien had been left with scarcely any free time, and lately he had allowed more issues of La Fronde to end up piled on his desk than he ever actually read. Adrien ducked his head sheepishly, which only prompted an amused smile from Alya.

"I'm sorry, Alya," Adrien apologized sincerely. "I've been busy lately, but I promise I'll read them soon."

Alya, far from being angry, sighed and shook her head. "Tsk," she scolded lightly. "You work too hard, Adrien! You should take fewer cases. It's not as if you need the money anyway."

Adrien smiled ruefully. "You know how it is, Alya. I can never turn down people who need my help."

"Yes," Alya agreed dryly, "nor can you turn down people who don't need your help."

It was true, much as Adrien was loathe to admit it. Alya kept wandering around the room, still searching carefully as though she expected to find a smoking gun hidden away in some secret compartment, and Adrien fell into step beside her.

"Well?" he inquired. "Who is this mysterious Ladybug, and why do you think he had anything to do with this?"

"She," Alya corrected smugly, "is a thief."

Adrien took another glance around the office, and its thoroughly undisturbed contents. "But nothing's been stolen," he pointed out.

"That's what you think," Alya countered. She smiled at him, a look so cat-like that Adrien half expected her to sprout whiskers. "The Ladybug is a thief, but when she steals, she takes only one item, and never the most valuable item in the room. In its place, she leaves this behind."

Alya produced from one pocket a thick black sheet, about the size of a playing card, with a stylized emblem of a ladybug painted on it in bright red ink. She handed the card over to Adrien, who studied it carefully.

"And you found this here, in M. Kubdel's office?" Adrien asked, arching one brow.

"Well... no," Alya admitted. "But, according to his daughter, Kubdel kept his pocketwatch with him absolutely everywhere—and see, it's missing from his body!"

Adrien looked curiously over at the body. It was indeed true, there was no sign of watch or chain on the man.

"It still seems a bit premature to attribute this alleged crime to your Ladybug," Adrien pointed out.

Alya pouted at him and folded her arms over her chest. "I forgot what a dreadful spoilsport you could be," she huffed.

"Alya," said Adrien plaintively, "there's no sign of foul play. He has a flushed face, mottled fingertips, protruding arteries—all the classic signs of apoplexy. He was getting on in his years, and it seems that it was just his time. His watch will no doubt turn up sooner or later."

"You're never any fun," Alya protested, but she seemed to accept his explanation, for she sighed heavily and headed for the door. Adrien followed after her.

"Thank you, officers!" Alya said cheerfully to the policemen as they passed by. The policemen did not look very happy to be thanked, and only watched in stony silence as Adrien and Alya exited Kubdel's office.

"News must be slow, if this is the kind of thing you've resorted to chasing after," Adrien remarked.

"You wouldn't know, since you haven't been reading my articles!" Alya teased. "But yes, that was something of a disappointment."

They shuffled together to the exit of the building. It was quite chilly outside, though there was no snow, and Alya pulled her coat a little more tightly around herself as they stepped out. The two fell naturally into pace alongside one another in a pleasant camaraderie.

"I don't know," said Adrien. "I generally find it preferable when deaths are not murders."

"Well, yes," Alya agreed, "but it's not my job to report on ordinary things! I cover sordid crimes and corruption and cover-ups."

"All very important feminist issues, I'm sure," Adrien remarked dryly.

"Crime is the most feminist issue," retorted Alya, "for no one is more victimized by it than women are." She looked pointedly at Adrien, who raised his hands up in a gesture of defeat. Satisfied with this reaction, she then added, "Anyway, I'm off to that new train station they're building along the river."

Adrien grinned. "Reporting on the Expo, Alya? How mundane! Isn't there some scandal out there that needs your attention?"

Alya smiled coyly at him. "A change of scenery can be nice, every once in a while," she said casually. "One can't cover conspiracies and murders all the time, you know! And besides, I've heard a rumor that some of the tradesmen are actually running a vast smuggling ring."

Adrien laughed out loud at that. "I should have known," he said.

They parted ways at the corner of Quai Voltaire and Rue du Bac, with Alya headed up along the river and Adrien west to his father's house.

Though he had been living separately from his father for several years now, he still made an effort to visit regularly, and they had established a custom of meeting for dinner every Sunday. Though his father was rarely affectionate, he placed a great deal of value on his family, as did Adrien—even if Adrien could not help occasionally chafing against his father's expectations.

Once he had crossed the river, it was only a short walk to his father's home, over in the neighborhood of Les Invalides. There, nestled in amongst the stately mansions of the old aristocracy, was the ancestral Agreste house, an aged building that had been designed in the classical style. Coming up upon the building, Adrien was struck by the thought that it looked uncomfortably grand. Though he had lived there his entire childhood, it had never felt very welcoming. The building was a relic of a bygone era, and something about it had always felt dead and cold, almost as though it were a living history museum.

While reminiscing on these thoughts, Adrien made his way up to the front entrance. His father's housekeeper, Nathalie, met him at the door. She was a cool, serious woman who rarely smiled. She greeted him with a stiff, "Good evening, Adrien," and the slightest nod of her head.

"Evening, Nathalie," said Adrien. "Are you well?"

"Perfectly," she said crisply. She moved as if to leave, but hesitated a moment. "I see you're wearing the ring your father gave you," she said.

Adrien glanced down at his hand. He was indeed wearing the silver ring that his father had gifted him for his birthday. It was a rather simple band, devoid of ornamentation, but he appreciated it nonetheless, as he did all gifts from his father. Although, admittedly, he would have preferred it if the gift had come directly from his father instead of being passed to him through the household staff.

"I am," said Adrien. He thought he detected something unusual in Nathalie's demeanor and asked, "Is there something wrong with it?"

"No, of course not," said Nathalie. Then she did leave, returning to her other household duties without so much as a goodbye. Adrien, who was rather used to this kind of behavior, did not take Nathalie's coldness personally. It was simply her nature.

Adrien's father, likewise, could be a very cold man. When Adrien entered the dining room, he greeted his father politely, and his father greeted him back, but after saying their hellos they quickly lapsed into silence. Although Adrien cared deeply about his father, they had little in common, and conversations between them were always sparse.

Dinner was served, and Adrien had made his way through most of the meal before his father said anything of any consequence.

"Adrien, I can't help but notice," he said, "that there is blood on your sleeve."

Adrien glanced down at his sleeve and, indeed, there was a small, brownish smear of blood marring his cuff.

"Ah," said Adrien awkwardly. The stain was a leftover memento from an overly exciting forgery case that morning. "I was working a case earlier."

"Working, on a Sunday?"

"Crime often does not observe the Sabbath," Adrien pointed out mildly.

"I do hope you are unharmed," the elder M. Agreste said. He even paused long enough in eating his roast chicken to look his son over. "I worry about this career of yours. You're always off gallivanting with thieves and prostitutes and feminists."

"The feminists are actually quite nice," Adrien offered hesitantly, but his father only scowled.

"I would prefer it if you settled into something a little more... respectable," his father said. Adrien steeled himself for an argument, afraid that this was the start of another row, but his father surprised him. "That being said, I have heard that you truly are an excellent detective."

"Have you?" Adrien asked sincerely.

"Perhaps you could help me with something," his father continued, "for the police have been of little assistance on this matter."

"Of course, father," said Adrien. "What do you need?"

"A few weeks ago one of the kitchen girls absconded with some of your mother's old jewelry," his father said. "It's not worth anything, really, but it has sentimental value. The girl's name is Marie Dupain, but the police have not been able to find her."

"I'll see what I can do," Adrien said.

They finished the rest of their meal with hardly any more conversation and, after a feeble attempt at playing chess with his father, Adrien departed for his own home.

Adrien rented a small living space in Les Halles, a modest quarters in an area mostly inhabited by middle-class shopkeepers and government clerks. It was quite unlike the grandiosity of his father's home in the Faubourg Saint-Germain, but the simplicity rather suited him. There he had just a few small rooms and lived entirely on his own, without the constant hovering presence of his father's household staff.

He often met with clients here in his own home, but on this evening he had no meetings scheduled, and so he was quite surprised to find a young woman loitering in his doorway with her knees drawn up to her chest. She was quite small and brown-skinned, and her eyes looked like they were red with crying. At the sight of him, she leapt up to her feet, and snarled ferociously at him, "Are you the detective?"

"I am," Adrien answered nervously. He was a little afraid that the woman would strike him, but she made no motion to attack.

"That journalist woman told me about you," said she, "and I need your help."

Adrien walked cautiously past the young woman and to his front door, which he unlocked and held open for her. She swept inside, collapsing immediately into the nearest armchair. "It's my father, you see," she explained with a tearful warble in her tone. "You were there earlier, at the museum, weren't you?"

It was then that Adrien realized that the young woman before him must be M. Kubdel's daughter, the one whom Alya had been speaking of earlier.

"I was," Adrien confirmed cautiously, "but I'm afraid there was nothing suspicious about your father's death."

"There was, though!" Mlle Kubdel protested vehemently. "His pocketwatch is missing! The police won't listen to me, but he carried it with him everywhere! It's an old family heirloom and it was very dear to him, and I cannot think that it is a coincidence that it is gone now."

The woman seemed on the verge of tears again, and Adrien felt a swell of sympathy for her, even if he was not swayed by her argument. "Perhaps one of the officers took it," Adrien suggested. "I can ask around and see if anything turns up."

If anything, Adrien's sympathy seemed to anger Mlle Kubdel further. "Why would they take only his pocketwatch, then, and not any of the dozens of more valuable artifacts left behind in his office? And why would a perfectly healthy man drop dead for no reason?"

"Apoplexy can often strike without warning."

"And can you tell the difference between apoplexy and poisoning?" Mlle Kubdel spat back.

"Mlle Kubdel—"

"Please," she begged him. "We don't have much, but my brother and I will scrape together every cent we have if you help us. I know that there's something strange going on here, if you would only just look!"

Adrien sighed heavily and reached for a pad of paper. "Very well," he said, persuaded more by her emotionality than by her offer of money. "I will take another look at your father's case—but I cannot promise that I will find anything out of the ordinary."

Despite Adrien's cautious warning, Mlle Kubdel was so delighted that she leapt to her feet. She looked for a moment as though she might leap over his desk to embrace him.

"Oh, thank you," she cried out. "Thank you, thank you!"

He then spent a quarter of an hour asking about her father, whether he had any enemies and what his pocketwatch looked like. Afterwards, once Mlle Kubdel had departed and Adrien was left alone with his thoughts and a disorganized sheet of hastily jotted notes, he found himself possessed with a sudden restlessness. Although there was no need to get started on the case straightaway and the hour was late, Adrien was eager to begin investigating. Despite the night, he decided to pay another visit to Kubdel's office in the Louvre museum.

The old museum was dark and quiet after hours and, once admitted, Adrien had not been expecting to see anyone at all. So he was quite surprised when, upon opening the door to the deceased M. Kubdel's office, he found someone already there.

The intruder was a young woman, a petite girl with an easy grace to her movements. Kubdel's body had since been removed from the office, and she had been studying the space where it had lain when Adrien walked in. Upon hearing the opening of the door, she straightened slightly, her head tilted to one side in a silent question. She was no taller than Adrien's collarbone, yet she carried herself in a way that made her seem somehow larger. Her features were partially concealed by a hood and a half-mask, but Adrien could still make out the frown on her lips.

"Good evening, mam'zelle," he said politely. "I suppose you are also a detective, then?"

"I suppose I am," the woman said hesitantly. Her voice was low and clear, and carried no trace of an accent to hint at her origins.

"And where is the pocketwatch?" Adrien asked.

"Already sold, I imagine," said the woman. "I have no leads on it. It could be halfway across the continent by now, for all I know."

"So you weren't the one who stole it, then?"

"I was not," she confirmed. "But you still suspect me, don't you?"

Adrien closed the door behind him before taking a few more steps into the office, coming to a stop near the center of the room. "It is awfully suspicious to find a masked stranger rummaging around a dead man's office on the day of his death."

"Yes, quite suspicious indeed," the woman agreed wryly, "and I must admit that I am curious about why you are here."

"I've been hired by Kubdel's daughter to investigate his death," said Adrien. "But who, I wonder, has hired you?"

At that, the woman smirked slightly. "I hired myself."

"And what have you discovered?" asked Adrien.

The woman's smile morphed from sly smirk into genuine amusement. "Ah, many things, my good sir," she said. "I know that the late M. Kubdel was left-handed, and passably fluent in six languages, and dyed his hair with paraphenylamine. I know that he made himself an enemy of a very powerful man."

"Is that so?" asked Adrien.

The woman reached for a teacup, the very same that Alya had picked up earlier. It was still half-full of tea, left undrunk and uncleaned in the chaos of the day. "Smell this," she said, and passed the cup to him. When Adrien lifted it close to his nose, she said firmly, "Careful. It is quite potent."

Adrien obliged her, carefully wafting the scent with one hand. Though the tea was quite cold and its scent had faded, he could still faintly detect a sharp, familiar odor.

"Anise?" he inquired, passing the cup back to her.

"Not quite," said the woman. "Liquorice root. Though quite harmless in its normal form, a talented chemist can distill it into a powerful poison capable of stopping a man's heart."

"So Kubdel was murdered," Adrien said wondrously.

"Yes," said the woman, "and if I were you, I wouldn't get involved."

Adrien arched a single eyebrow. "You say that," he countered, "and yet here you are."

The woman looked at him sternly. For a moment, the moonlight through the window struck her at precisely the right angle, and Adrien was struck by how vividly blue her eyes were. "My involvement is not by choice," said she, "and my enemies are very dangerous. I'd advise against making them your enemies too."

Her words were dark and serious, and the tone of them sent a chill down Adrien's spine.

"Who are you?" he asked, knowing that he would get no answer even as he asked it.

"A stranger," she answered, "and for your sake, I hope it stays that way."

Then, without any warning, the woman crossed over to the open window in Kubdel's office and slipped soundlessly out of it. Adrien rushed forward, peering out into the dim evening light, but could not see where she had landed.

"What a strange, fearless woman!" Adrien muttered to himself. Though he had seen circus acrobats and young daredevils take leaps from such heights, he himself found the distance between Kubdel's second story window and the ground below to be uncomfortably long.

He returned his attention to studying Kubdel's office, but his thoughts kept returning to the mysterious woman. She apparently knew about the dead man's missing pocketwatch, though she claimed innocence of that particular crime. And although Adrien had every reason to doubt that, he found himself inclined to believe her. Mysterious though she had been, Adrien rather thought that he had detected sincere conviction in her strange, cryptic messages.

When Adrien finally slunk out of the Louvre, it was in defeat. The only real lead that Adrien had was Kubdel's mysteriously missing pocketwatch, but he feared that he would find no answers there. The mysterious intruder had insinuated that he had been killed over the pocketwatch, and yet the facts did not seem to add up. If Kubdel's killer was looking for money, then there were plenty more valuable things to be found within his office. Adrien was forced to conclude that there was something particularly special about this pocketwatch, though according to Mlle Kubdel there was nothing remarkable about it, save that it had been very dear to her father.

And where would one sell such a pocketwatch, in any case? Adrien mulled over these thoughts for the rest of the night, getting hardly any sleep at all, and awoke uneasily the next morning. He remained deep in thought over breakfast, even as he dutifully scanned through Monday's edition of La Fronde. The second page of the newspaper featured one of Alya's salacious crime reports and, thinking back to his encounter with Alya the previous day, Adrien was struck with a sudden thought.

He wasted no time that morning before heading over to the Gare d'Orsay, where he began to seek out Alya's alleged smuggling ring. The station, located at the site of the former Palais d'Orsay, was being built in preparation for the upcoming 1900 World's Fair, and was coming along quite well. The construction zone was brimming with workers of every sort, carpenters and metalsmiths and mechanics alike, and Adrien found himself filled with a quiet admiration for these talented craftsmen, all working so beautifully together in concert.

He then set to work, and it was a surprisingly easy business for him to at last to be directed to one Maximilien Kanté, an engineer. He was from the French Sudan colony but had been trained in Switzerland; according to colleagues, his mechanical talent was unparalleled, and he was supervising work on the station's clock tower. There were also a fair few rumors that he had many foreign contacts, in both Switzerland and the Sudan as well as farther afield, and that he was the sort of person who could help you acquire something without the hassles of customs and tariffs.

Kanté himself was a short African man, bespectacled and serious, and looked somewhat suspiciously at Adrien as he approached.

"Are you M. Kanté, the engineer?" Adrien asked.

"I am," he confirmed. His voice was deep and he had a pleasant, melodic accent. "Is there something I can help you with?"

"I have heard a rumor," said Adrien cautiously, "that you are a man with connections to the black market."

His words clearly had an effect on the man. Kanté stiffened noticeably and bared his teeth in an unfriendly grin. "Perhaps you have misunderstood a joke," he said; "the only black thing here is the color of my skin."

"That's clever," Adrien said, with genuine appreciation for the pun. Then he glanced quickly over one shoulder and leaned in nearer to Kanté, to speak in a low voice. "I'm not here to turn you over to the authorities," he promised. "I'm asking for your help in a murder investigation."

Kanté lifted his eyebrows, and Adrien continued. "A pocketwatch was stolen from a man on the day of his death. I've reason to believe that it has some value on the black market, and I need your help tracking it down."

Kanté's expression grew thoughtful. "A watch, you say? Perhaps I could find such a thing. But obtaining it will not be easy... or cheap. And it would be illogical to spend so much money on something I could not resell."

Adrien, understanding his meaning, sighed quietly. "I can compensate you appropriately, of course," he said.

The two negotiated prices for a while longer, until Kanté was satisfied with their deal. "Very well," he agreed. "I will do everything in my power to find this missing pocketwatch of yours."

Then all Adrien could do was wait. Fortunately, it was only two days later that Kanté wrote to him with news of success. They met soon after, and the appropriate money was exchanged. When Kanté finally passed the watch over to him, Adrien could not help but marvel at it. It was a perfectly ordinary thing, small and silver, and Adrien could not deduce what was so valuable about it.

Kanté was little help on that front as well. "I never met the seller in person," he said. "The man would only work through proxies and secret drop-points. There is clearly something very strange about this watch of yours, but I could not discern it without revealing my true mission."

That was disappointing news, for it left Adrien with a very cold trail, but he could hardly fault Kanté for it. "Thank you for your assistance," he said earnestly. "It means a great deal to me—and to the victim's family."

"I am glad that I could help," Kanté replied, "though, frankly, I am eager to wash my hands of this. I do not typically deal with murderers and thieves, and it was a very unpleasant business."

Kanté then departed and Adrien met with the young Mlle Kubdel immediately afterwards. Though he had made little progress in finding her father's killer, she was delighted to have the watch returned.

"Be careful with that," Adrien warned cautiously. "I don't know what it is, but someone may have killed your father in order to obtain it, and they're still out there somewhere. If anyone learns that you have it back, they might come looking for you or your brother."

"You'll find them," Mlle Kubdel said confidently. "You will find justice for my father, I know you will."

Adrien opened his mouth to protest, but Mlle Kubdel quickly added, "And until then, I promise I will be discreet."

She thanked him again, most profusely, and saw herself out. Adrien had intended to return to the work of tracking down M. Kubdel's killer, but he scarcely had a moment to himself before another guest arrived at his doorstep.

Aurore Beauréal was an old acquaintance of his, her father and his father having had business together some years ago. In general, the elder M. Agreste disapproved heartily of the Beauréals, who were part of the new bourgeoisie and dabbled in the occult, but Adrien had always gotten along well with Aurore.

"Hello, my dear!" she crooned, with perhaps a bit more familiarity than was warranted. "I do hope you have been well."

Before Adrien had time to form a reply, Aurore continued on, "I have heard from your father that you are a detective of immeasurable talent, and I was hoping you could help me recover something that was stolen from me—a lovely blue silk parasol and, well, you know how the Parisian police are—so, can you help?"

"Well, I can always try," Adrien said, still trying to parse her sentence.

"Oh, excellent!" said Aurore. "The thief stole into my home in the middle of the night, you see, and ran off with the parasol. They left this behind in its place."

Aurore produced from her pocket a small black card. She passed it over to Adrien, who was quite surprised by what he saw.

Painted on the center of the card, in bright red ink, was the unmistakable image of a ladybug.