A/N: Written for Ralinde's Missing Moments Competition and for Silvery Wind's The Harry Potter Day Competition 2015.

Thank you, as always, to my lovely brother for beta reading this.

Word count: 2781

Sunshine lit up the library like an old friend wanting attention, warming the room's inhabitants even as it distracted them from their work. Penelope set her quill aside and, closing her eyes, allowed herself to bask in its radiance. Her whole body felt more relaxed under its scrutiny, almost as if it were burning up all of the tension within her until only tranquillity and ashes remained. Neither the intensity of sixth year subjects nor the ubiquitous threat of this Chamber of Secrets business mattered to her anymore. She could only imagine how much better it would feel if she were actually outside, sitting in the Quidditch stands under the sun's direct gaze.

The decision to skip the morning's game had been an easy one when she'd planned her weekend the night before, but it was much harder now that she could feel what she would be missing out on.

I need a break in any case, she abruptly decided. High marks aren't worth it if you drive yourself insane in the process; my Herbology essay can wait until this afternoon.

She hurriedly but neatly packed her bag before swinging it over her shoulder as she made her way out of the library. The only thing that kept her from breaking into a jog was the knowledge that it would disturb the few students who had decided to persist through the warm temptation and, likely, invoke the censure of Madam Pince.

As she neared one of the more out-of-the-way exits, the sound of insistent and distressed muttering caught her attention. The outside world beckoned to her, but she forced herself to do her duty as prefect and investigate. Following the noise, she made her way to the relatively isolated table that she knew to be Hermione Granger's favourite reading spot. Bookshelves acted as a noise buffer between it and the other tables, but it was still close enough to the main aisle that the girl would have fairly easy access to the different facilities. Penelope rather suspected that one of the main attractions of it was that the fact that it was so far removed from the main part of the library meant that it was easy for the librarian to forget the girl altogether when it was time to close the library for the night.

Sure enough, the Gryffindor second year was immersed in a book. Pieces of scrunched-up parchment dotted the desk around her. She was leaning forward as if she were reading a thriller that she felt compelled to draw closer to, her eyebrows puckered together and her hands gripping the table tightly in an obvious display of concern. As she read, she ranted to herself about something to do with snakes and pipes. The sunlight cast a golden glow over her, almost making her unwavering focus more unnerving; Penelope was used to seeing classmates in a frenzy to complete an assignment the night before it was due, but it was strange to see that translated over to a daytime situation.

Sometimes the light can be scarier than the dark, she mused. Sometimes it reveals things you'd rather not know, like how obsessive we can get over ultimately meaningless things.

"Hermione," Penelope said in her quiet inside-a-library voice, before repeating it again, louder and more insistently, once she realised that the girl hadn't heard her the first time.

Hermione visibly recoiled from her at the noise before looking up and, upon seeing whom it was, smiling sheepishly. "Oh! Penelope. Sorry, I didn't realise it was you."

"I'd hope not, after a reaction like that."

"I've been antsy lately," she said vaguely, by means of an explanation, before returning to her book.

Penelope was determined not to let her. "I think we all have. Perhaps you should take a break; it's a lovely day outside, and it might do you good to forget about things for a while."

"I'm almost done here."

The older girl watched her unobtrusively for a few seconds. She would usually respect a student's wishes and leave them be, but Hermione's muttering concerned her. Penelope couldn't remember snakes, let alone pipes, ever being mentioned in class, and she was rather worried that Hermione might be ahead of her on the study-your-way-to-a-breakdown front. It wasn't an unusual phenomenon amongst the first, fifth and seventh year Ravenclaws, so she was used to identifying the early warning signs. "Alright, then; can I help? You said something about snakes and pipes, didn't you?"

The Gryffindor surveyed her suspiciously, apparently gauging her genuineness and weighing up whether or not to accept her offer. "I suppose," she said after a moment. "As long as you promise not to tell anyone else about it."

"As long as keeping it a secret won't hurt anyone, I'll respect your privacy."

Hermione surveyed the area around them with a watchful gaze, as if she honestly expected that there might be other students who had chosen to forgo the Quidditch match to study. The responding laugh that Penelope was struggling to contain – it was always amusing to talk to younger students and see how seriously they took things that seemed so minor to her – caught in her throat at the girl's next whispered words. "I've been trying to work out what the monster in the Chamber of Secrets is, and I think I just had a breakthrough."

"Tell me about it." Penelope lay her bag on the table and drew up a chair to sit in, leaning forward with her arms resting on the wooden surface once she was seated in a conscious attempt to encourage Hermione to talk.

The girl hesitated yet again, biting her lip as she stared at her with an assessing gaze. Apparently, Penelope wasn't found wanting, for she eventually released her lip and said in an onslaught of words that made it seem as if she thought that getting it out quickly might negate any associated sense of betrayal, "You know that Harry's a Parseltongue; everyone does by now. Well, he's been hearing things that no one else could all year. Ron and I thought he was going crazy, but I worked it out today… When he said he could hear it again, I noticed a hissing noise. Every time he's said it, I've heard that hissing; I always assumed it was just the plumbing, but what if it isn't? I think it's a snake of some sort."

"And it's getting around through the pipes?"

Her head nodded vigorously, sending tremors through her bushy hair. "Yes, exactly."

"It's a decent theory," Penelope replied thoughtfully. "The idea of it being a snake fits in with the heir of Slytherin thing as well. It's much better than what people have come up with before. But how can a snake have these kinds of – Oh."

"You've thought of something already?" Hermione asked, her face a battleground for excitement and disappointment as she stared up at Penelope with an eager gaze. "That was where I kept getting stuck."

"Maybe. Just give me a minute." The Ravenclaw girl vacated her seat and weaved her way through the labyrinthine bookshelves of the library until she reached the section on magical creatures. Well aware of the book she needed, she sifted through the old and often ratty tomes until she found the one titled Most Macabre Monstrosities. Once she had the book in hand, she started making her way back to the table, leafing through the pages as she went.

Hermione Granger looked to be almost bursting with energy when she arrived in the small recess once again. "Well?" the girl demanded.

"I did a Care of Magical Creatures assignment on the XXXXX-rated magical creatures last year," she explained, trying to buy herself some more time. "This was the only reliable source on the topic. Basilisks are one of the worst of the lot. They can kill with a single stare; all it takes is it meeting the gaze of another living thing. Here we go; read this."

Hermione took the proffered book impatiently and immediately threw herself into reading. As she finished, her first words were, "But none of the victims have died."

"There are a lot of unsubstantiated legends about basilisks as well. The book didn't explore them – it's more academic – but the main one is that the intensity and effects of its gaze can be diluted if its path is somehow obstructed, such as through…"

"Reflection," Hermione cut in, her eyes wide as she realised where it was going. "The water on the floor, the camera lens… None of the victims were subjected to the basilisk's gaze directly. And," she added, glancing back down at the book, "it would explain why the roosters died. But why haven't I heard about it before?"

"There haven't been any sightings in centuries. People generally know that they're dangerous, but it's been so long that no one is really aware of them."

Hermione glanced off to the side, apparently lost in thoughts. For the first time since she made the discovery, Penelope had the chance to really think about what it meant. She felt like her brain was functioning slower than it usually did, as if it had shutdown from shock and was still cultivating the power needed to think properly again. Despite her mental inertia, one thought got through.

This was bad.

The XXXXX category was used to denote magical creatures that were known wizard-killers. They were the type of being that could wipe out an entire wizarding village on their own without much difficulty. They were the type of being that needed a whole team of trained, specialised wizards and witches if they were to face any kind of real trouble.

And there might be one loose in the school.

"We need to tell a professor," Penelope said, pulling the book back towards her and ripping out the page. "Right now. Can I borrow your quill?"

"What did you just do?" Hermione asked in outrage, having only just noticed her companion's actions. "You just ruined – "

Penelope stared at her incredulously. Was she really protesting about the maintenance of a book when such a dangerous beast might be loose in the castle? Penelope well and truly understood the desire to respect books, but the reaction seemed excessive, even to her. "I can repair it later," she said dismissively. "I'll even teach you the spell if you want. But we're both Muggle-borns and there's something out there targeting us and I don't want to risk it getting to us before we can get the information to somebody."

Nodding in understanding, Hermione pulled the torn page towards her and scrawled the word 'pipes' down the bottom of the page. "Do you have something I can conjure into a mirror? A piece of glass, perhaps, or something transparent? I was going to start practicing the spell to make other objects into reflective surfaces in a few months, but then I thought it might be better to start researching the possible elective subjects for next year."

"I'll do it," Penelope offered, before making a complicated little gesture with her wand and, pointing it at a blank piece of parchment, saying clearly, "Repercutio."

Colour fading in places and darkening in others, the parchment grew and thickened like a baking scone until all that remained was a small but ornate handheld mirror. Its glass was sheathed in a dark wooden surface with eagles etched into it.

"You're marked on intricacy as well as function," Penelope explained, feeling slightly sheepish at her overachievement. Hermione, however, merely looked impressed as she picked up the mirror and, murmuring what sounded an awful lot like the incantation, examined it carefully.

Deciding to leave her to it, Penelope hurried off to return the book. Fortunately, Hermione appeared to be ready upon her return. Her ink bottle, quill and unused parchment were stashed on the nearest bookshelf.

Noticing the direction of Penelope's gaze, Hermione explained, "I'm the only one who ever comes here, and leaving them here means that I can duck in at any time."

"Alright," Penelope said, surprised by this indication of exactly how dedicated the younger witch was, as she hoisted her bag over her shoulders. "Shall we go, then? We might as well head for the Quidditch pitch; it's the closest place where we'd be guaranteed to find a professor, and the basilisk is unlikely to go out in the open like that."

Unbeknownst to them, however, someone had witnessed Hermione's departure for the library that morning and had anxiously followed her there, hiding in the shadows in the way only they could. That someone had listened in on their conversation, scribbling down notes in an old but surprisingly well-preserved diary. And they had received advice in return. As soon as the young witches started to hit upon the truth, their silent observer's face had gone blank and, with glazed-over eyes and a flat expression, they had raced to the girl's bathroom on the second floor to release the monster that lay therein.

As they left the library to make their way through the winding halls of Hogwarts, all they knew was that they had to get to a professor.

Their gazes were both steadfastly directed at the ground in front of their feet, and Penelope noticed Hermione scrunch up the piece of paper in her hand as they walked. It seemed like a nervous tic; she knew enough about the Gryffindor to know that she wouldn't consciously defile the book further, fixable though the action was. "We'll be fine," she reassured her.

"I know," Hermione said, but her voice shook nevertheless.

"Do you want me to take the mirror?"

"No, I'll keep it. We learned all about angles and reflection in primary school. Well, they learned about angles; I learned about reflection on my own."

"Tell me about it," Penelope directed her, needing to hear human speech to remind her that she wasn't alone.

"Angles or reflection?"

"Anything."

"Well, it starts off with a ray of light called the incident ray," Hermione explained, her voice animated despite her downturned eyes. If she'd had free hands, Penelope was sure she'd be gesturing wildly to illustrate her point. "It hits the surface of the object and reflects off it in a way that the angle between the incident ray and reflected ray could be split in half by a thing called the normal line, which is perpendicular to the original surface. When you're trying to see around a corner with a mirror, you'd therefore need the distance between your eyes and that normal line to be equal to the distance between the spied-upon object and the normal line."

The words were coming out too fast, almost as if the information were a guilty confession made to an injured party, and it felt like a strangely complicated explanation for what she'd imagined would just involve adjusting the angle of the mirror until you were sure you'd seen the whole corridor. Still, it soothed her fears like a lilting bedtime story lulling her into complacency; Hermione seemed to know what she was doing, and Penelope was certainly not alone.

"See?" Hermione asked as she tilted the mirror around the edge of the next corner, her gaze securely fixated on it as she surveyed the corridor. "You angle it so that – " The young witch froze with a sharp intake of breath.

"What is it?" Penelope whispered, concerned. "Is someone injured – "

She manoeuvred herself around the obstacle of Hermione's head until she too could peer into the mirror's reflective depths. The small oval depicted what appeared to be an interlocking network of green scales. It was as if it were a beacon signalling the presence of dangerous rocks and tides to incoming ships. "Oh."

"We need to find another way around," Hermione murmured, still staring at the mirror in shock despite her mind's insistence that her body was being stupid and should just listen to its commands to move as far away from that thing as it could. "Move slowly and quietly. I read once that snakes sense and strike at fast movements. If it notices us – "

To their ill fortune, however, their version of rocks were in fact broken off pieces of icebergs that drifted about at the whims of the tide. As they stood transfixed, they heard an eerie hissing noise, and the serpentine body started to coil and twist and move in place. Neither girl was sure exactly what it was doing. Not, that is, until their entire vision changed. The basilisk's head came into view, and they were suddenly confronted with the most brilliant pair of yellow eyes that Penelope had ever seen.

A/N: I read a tumblr reblog that queried the idea that Hermione would rip a page out of a library book. Their theory was that Draco had heard about the basilisk from his father and anonymously slipped her the information, but I think it's more likely that Penelope was merely more involved in the discovery than Harry thought she was.