Dolores Umbridge's compact wand twitched back and forth, almost in regular rhythm, as the Fifth Years departed Hogwarts castle for the steep trek down toward Hagrid's hut for Care of Magical Creatures class. Gryffindors and Slytherins alike flinched as Umbridge's spells tightened ties, tucked in shirttails, lengthened skirt hems, and forced several handholding couples at least three arms-lengths away from each other. Above the groans and grumbles, Umbridge continued to smile her tight, self-satisfied smile, while her devoted cohort, caretaker Argus Filch, smirked admiringly in the background.

Ron Weasley shot an angry look over his shoulder at the aggravating woman, and once he had descended below the pink pain-in-the-arse's line of sight, he wrenched loose the tight knot of his necktie.

"I'd thought she'd let up after the first few days," he muttered, his sausage-scented breath fogging slightly in the chill September morning air. "But this is the second week…" He struggled against the weight of his school bag and finally succeeded in yanking his shirttail out of the waist of his uniform slacks. "D'you think old toadface will be this bad all year?"

Harry Potter shook his head, partly in answer to Ron's complaint, partly to assist his fingers in loosening the tie around his own neck. "It doesn't look promising," he said gloomily.

Ahead of them, Hermione Granger's brown hair flounced with every downward step. A small cloud of fog formed around her head, and as Harry and Ron passed through the thin brume, her words seemed to still hang in the misty air: "…-try was interfering."

"Yeah, you told us," Ron conceded grumpily.

Down, down, down the hill they went. Every so often, Harry cast a quick glance back over his robed shoulder to keep track of the Slytherins uphill of them. Granted, the worst of the lot – Draco Malfoy and his usual goons – were walking ahead of Harry, Ron, and Hermione, but Harry couldn't really trust any of the Slytherins not to suddenly decide to shove someone over, causing the entire group of students to topple like dominoes down the steep, narrow path. He was surprised it had never happened in the previous four years he'd been at Hogwarts, but his rather bizarre experiences since starting school had taught him emphatically that there was a first time for everything.

Hermione stopped abruptly and Ron nearly walked into her, almost setting off the domino effect on the spot.

"'Mione! What the – "

And then he saw what she was pointing at. Or, rather, whom.

"Snape!" she hissed under her breath. "Down there with Professor Grubbly-Plank."

A tall, elderly witch with close-cropped gray hair stood in front of Hagrid's hut, smoking a pipe while she awaited her students' arrival. Exhaling a thin stream of smoke, she leaned her head intently toward that of the younger, dark-haired Potions Master. As the students approached, she waved her wand to extinguish the pipe and tucked it into a pocket in her dusty-hemmed blue robes.

The trio of Gryffindors stepped aside to allow several other students of both Houses to pass down the path before they brought up the rear of the straggling line of pupils arranging themselves in a semi-circle in front of Hagrid's pumpkin patch. Harry could tell that his friends felt as he did, missing Hagrid's vast presence, and the hut's smokeless chimney only emphasized the half-giant's absence.

Professor Wilhemina Grubbly-Plank lifted her prominent chin and ran a practiced eye around the group of students. "Miss Greengrass?"

"She will be joining us later," Severus Snape's deep baritone informed the other teacher. "Her absence is excused, due to a prior appointment."

Ron snickered quietly, and Harry knew it was due to the same sight which had just caused Hermione to cough into her cupped hand: Snape's breath had fogged even more than the students' or Professor Grubbly-Plank's. Seeing was believing, and on this chilly morning, Snape had inadvertently just proved that he was full of hot air!

"Very well," said the CMC professor. "Class, we have a new, and somewhat disturbing, Magical Creature to study today. This one is not covered in your textbook, so I shall expect you to listen closely and take detailed notes."

She waved her wand and a double row of benches arranged themselves in a semi-circle. The Gryffindor and Slytherin Fifth Years quickly sat and pulled parchment and quills from their school bags. When the bustle had died down, Professor Grubbly-Plank announced, "I am turning this part of the class over to our guest lecturer, Professor Snape. He has done more research about this creature than any other member of the Hogwarts staff, thus far. Professor Snape," she said, gesturing him forward, even as she seated herself on an end bench with the students and organized her own parchment and quill for note-taking.

"Thank you, Professor," Snape said quietly. His black eyes slid carefully over the faces of the assembled students, and the gravity of his expression caused several of the teens to shudder slightly. They were accustomed to a sneering, sarcastic, overbearingly-snide Snape; this serious side of Severus Snape struck an uneasy chord deep within the students.

"As you know, my field of expertise is Potions. However, it is precisely due, in part, to the illegal use of a particular potion that this creature even exists today. To put this information into a historical context: Back in 1984, during an ill-advised experiment, a particularly-dunderheaded Frenchman used a Dark potion – which I shall NOT name – to facilitate illegal Magical crossbreeding between two non-Magical creatures, namely a common gray squirrel and a vampire bat."

The collective gasp from the students created a small fogbank beside Hagrid's hut.

"Quite," said Snape, assessing their shocked expressions.

Hermione's hand shot into the air.

Snape's lips tightened. "Yes, Miss Granger?"

"But WHY? WHY would anyone do something that … bizarre?"

"I just stated that he was a dunderhead, Miss Granger. A graduate of Durmstrang, no less."

Hermione's eyes grew round, but she kept her silence this time.

"Suffice to say, this French … 'scientist' … did not stop with a single experimentation. The idiot became so enamored with his success that he REPEATED the process. MULTIPLE times."

Snape allowed the students to absorb the implications.

Once again, Hermione raised her hand, but this time it crept upward, almost as if afraid of the question she needed to ask.

When Snape merely nodded his dark head in her direction, she licked her lips before speaking. "What… What happened to these creatures, Professor? Did they … survive beyond the experiment?"

Uncharacteristically, Snape sighed. "Unfortunately, they not only survived under laboratory conditions – they thrived. The French wizard discovered rather quickly that these new creatures were quite capable of breeding true to type, and they continued to do so under his devoted care for several years."

When he whirled in anger, Snape's robes kicked up a bit of dust from the hard-packed dirt in front of Hagrid's doorstep. "Eventually, Le Bureau des Affaires Magiques – the French equivalent of the British Ministry of Magic – got wind of this imbecile's doings. Following an extensive investigation, they ordered him to destroy the creatures, which numbered several hundred by that time."

Hearing gasps of dismay from several of the female students from both Houses, Snape growled, "Don't misplace your sympathy too soon."

Harry finally spoke up, asking, "What happened to the creatures, Professor? Did he … "

"He did not destroy them, Potter." Snape's trademark sneer mingled with fury, but for once, his anger was not directed at the boy. "He RELEASED them from the laboratory. Into the French countryside. Where they continued to feed and breed, and the creatures quickly began to create a nasty reputation for themselves."

"What kind of reputation?" blurted Ron.

Though Snape's glare grew ominous, the entire class could tell that the man was not angry at Ron, but at the French imbecile.

"Le Bureau des Affaires Magiques began referring to the creatures as 'les écureuils fatals' – the Fatal Squirrels."

"They KILL people?!" shrieked Pansy Parkinson, dropping her parchment and quill to the dusty ground. "Merlin preserve us!"

"Calm yourself, Miss Parkinson," ordered Snape. "There have been no reports of the Fatal Squirrels killing people. Yet. Thus far, we know that, individually, they have killed smaller animals, while group attacks have successfully destroyed mammals as large as horses."

"But COULD they kill people?" Harry asked urgently. "If they can kill a horse…"

Snape launched into full lecture mode.

"The Fatal Squirrels were released from a laboratory in the south of France, in the Provence region south of Lyon, specifically, and they were first spotted in the wild on the lower western slopes of the French Alps in 1987. They seem to have migrated steadily northward, keeping west of the Alps and following the Saone River, then crossing it and the Seine before traversing the Champagne region. The squirrels reached the area surrounding Reims around 1990. From there, they turned northwest, bypassing Lille, and headed for Calais. By 1992, they had achieved the British coast at Dover. Within two more years, there were also confirmed sightings near Folkestone."

Harry raised his hand. "You said squirrels were crossed with vampire bats?"

Snape nodded.

"Do they have wings? Did they fly over the French rivers and the English Channel?"

One of Snape's eyebrows rose, a sign of surprise at the Gryffindor's astuteness, blended with reluctant approval, although, in this case, the boy's supposition was off target. "They do, indeed, have wings, Potter. However, according to their French creator, the wings will not support their body weight for sustained flight. They can gain the treetops from ground level, and they are capable of gliding for short distances, but extensive winged flight is not possible."

Frowning, Harry pursued his line of inquiry. "So, how did they get here from France?"

Snape's frown mirrored his own. "The Magical Ministers from both countries speculate that they likely could have crossed rivers via bridges or by stowing away on boats. As for traversing the English Channel, our governments believe that the animals made use of ferries, or to a lesser degree, the new Chunnel trains."

"The what?" Draco looked utterly lost upon hearing the word "Chunnel".

Smirking, Snape replied, "Last year, in 1994, the Muggle train line operating between London and Paris began operation."

Draco snorted. "You can't run a train between London and Paris. There's no bridge. My father works for the Ministry of Magic. He knows these things."

Harry guffawed. "I guess he doesn't know everything, Malfoy, because the Muggles built a tunnel under the English Channel, and trains do run through it!"

"You're full of dragon dung, Potter! There's no such thing!" The blond Slytherin glowered up at Snape's looming dark figure. "Tell him, Professor! Put the half-blood in his place!"

Linking his hands behind his back, Snape strolled leisurely toward the nearest pumpkin. "Sorry to disappoint you, Mr. Malfoy, but the Muggles DID build a channel railway tunnel, and they refer to it as the Chunnel. Despite their care to avoid unwarranted transfers of wildlife from Britain to France and vice versa, no system is foolproof, particularly among Muggles, and it remains possible that a small number Fatal Squirrels may have hitched a ride on the trains running through the Chunnel, particularly since the Calais to Folkestone line went into operation."

After contemplating the pumpkin at length, the man continued, "Given the degree of Magic conferred upon the animals during their diabolical creation, it seems likely that they may embody a Muggle-oriented Notice-Me-Not spell or even a Muggle-repelling charm, either of which would prevent Muggles from spotting any furry stowaways inside the trains. However, we believe it more likely that greater numbers arrived unseen aboard Muggle ferries during the past few years. And, once here, they continued their northward migration through England toward Scotland."

"Scotland?" whimpered Ron. "Here? They're coming HERE?"

"In fact, Mr. Weasley, the Fatal Squirrels have already arrived north of the Border."

Harry swallowed. "How long until we could see one? Sir."

The dark man shook his head, causing his ebony hair to swing against his cheekbones. "Unknown, Potter, but the best estimate is near the end of October or the beginning of November."

"Are…" A new voice sounded behind Harry, and he turned to see Daphne Greengrass slowly sitting down beside Blaise Zabini. "Are you sure they're coming to Hogwarts?"

Snape sighed deeply. "Most likely, that will be the case."

"But why here, sir?" asked Daphne. "Why not London?"

"These creatures apparently feel an affinity toward Magic, Miss Greengrass. Though their ancestors were – for lack of a better term – Muggle animals, Magical spells, combined with potions containing Magical components, created the Fatal Squirrels, and – as Magical creatures – they tend to veer toward concentrated Magical power. They DID pass through London, and those which congregated in Diagon Alley were disposed of, for the most part. Several other locales with Wizarding populations have reported similar influxes, while neighboring Muggle towns have shown little evidence of their presence. Estrella's Strand, Godric's Hollow, Hangtree, and Corbin's Firth have encountered a disturbing number of Fatal Squirrels. And, given that Hogsmeade has an all-Wizarding population, with Hogwarts castle containing the most concentrated level of Magic outside of the Ministry of Magic and St. Mungo's Hospital, it is a fair bet that the Fatal Squirrels will ultimately head to this area."

"Did they get into the Ministry?" asked Ron. "Or St. Mungo's?"

"No. Both are top-security facilities, employing both strong wards and full physical lockdown."

"What about Hogwarts?" demanded Draco. "Can they get into the castle?"

Snape narrowed his eyes. "The wards on both the castle and the grounds have been strengthened, and they will be constantly monitored. However – with students routinely entering and exiting the castle for classes and other activities – Hogwarts does not enjoy quite the same level of security as the Ministry or St. Mungo's. The Headmaster has already conferred with the Head Goblin of Gringotts about their security, since several Fatal Squirrels managed to enter the bank's main lobby."

For the first time since they'd sat down, the entire class chuckled quietly, envisioning the scene of a battle between winged vampire-squirrels and outraged Goblins.

Hermione raised her hand. "What do they look like exactly? How do we identify a Fatal Squirrel?"

Snape's lips twitched. "They are essentially the same size as a gray squirrel, although their fur is verdigris in color, with a paler green belly."

"What?" asked Ron. "Verd-what?"

"Greenish-gray. Or grayish-green," Hermione whispered. "It can vary."

The redhead stared at her in disbelief. "Greenish … squirrels…"

"The animals have standard squirrel-like bodies, complete with bushy tail, but they also have the leathery wings typical of bats," Snape continued. "When not in use, the wings fold tightly into thin, twin 'sticks' attached just below their shoulder blades. Without the spreading wings, you would need to see the verdigris fur and pointed, bat-like ears protruding from the tops of their head as identifiers. The Fatal Squirrels also possess vampire-like fangs in the upper jaw, which they use to pierce their victims in order to lap up their blood. Combine these fangs with an ordinary squirrel's naturally-sharp teeth, and the Fatal Squirrels have been known to rip open raw flesh during their attacks."

"So they live on blood?" Harry asked, screwing up his face in revulsion at the thought.

"A mixed diet of nuts and blood, for the most part," Snape informed him, "depending on availability. Sources mention that the Fatal Squirrels appear to favor nuts, but if the supply runs short, they will then resort to attacking animals – mainly mammals – for sustenance."

Pansy looked up from her scribbled notes. "You said earlier that they hadn't killed anyone yet. But have they ever attacked people?"

Snape nodded, and the class moaned.

"In their migration, there have been various attacks on humans. For some reason, they have attacked more females than males, and all of the human victims have been Magical, rather than Muggle. That seems to emphasize their attraction to Magic, but it does not explain the gender differentiation. The animal victims have been primarily 'Muggle' – possibly due to greater availability – although several attacks on Magical creatures have been reported though the years."

Snape watched these latest facts find their way onto parchment. "You may also note that their eye color – according to human victims and witnesses of attacks – turns blazing electric blue when they become agitated, but is a dark blue, otherwise, when they are calm. They feed both by day and by night, so do not consider yourselves immune to attack based on daylight or darkness. As for defending yourselves, be aware that the Fatal Squirrels seem unaffected by Stupefy and Impedimenta." He sighed deeply, looking more disturbed than any of the students could ever remember seeing him. "Early reports also indicate that the squirrels seem relatively impervious to most Magical spells, be they defensive or offensive."

"What do we use, then?" asked Harry, clenching his quill in consternation.

"The Goblins at Gringotts reported that ordinary water seemed to slow them down, for some reason, so I would strongly recommend that all students practice Aguamenti."

And suddenly, Snape's wand appeared from nowhere, with a powerful jet of water spewing forth to wet down the dusty ground.

"The water doesn't kill the animals, but it appears to slow them down rather drastically. Since the Fatal Squirrels locomote as quickly on the ground as their Muggle counterparts, you would be well advised to master this Charm."

The Potions Master waited once again until all of the students' quills ceased scratching across parchment. Then, with a wave of his wand, he levitated a small log table which had been standing next to Hagrid's hut. He positioned the table directly in front of him. Upon the table sat a bulky, cloth-covered rectangular object.

"This," he said, placing his hand upon the cloth, "is a Fatal Squirrel."

Slowly, he lifted the fabric, and the students craned their necks to stare at the creature within the sturdy metal cage. Greenish-gray in color, the only aspect markedly different at first glance were its pointed bat-ears. Snape dropped a walnut through the top of the wire mesh of the cage, and the creature immediately snatched it up and began methodically gnawing at the shell in squirrel fashion. "You may observe the vampire fangs, which the animal often employs in breaking through the nutshell, as well as puncturing a mammal's skin."

Snape gently prodded the creature's left thigh with a twig, and the Fatal Squirrel turned sideways, away from the slight pressure, so the students could see the "stick" attached to its lower left shoulder blade. "Watch," instructed Snape, and he teased at the underside of the animal's "stick". Immediately, the wings expanded widely, bracketing the bushy tail tucked up against the animal's furry back.

"Wow!" breathed Ron. "That's wicked! But they still can't fly all that well? The wings look pretty big to me."

"A squirrel's body weight is far heavier than a bat's would be for that same wingspan, Mr. Weasley. Fatal Squirrels depend on their leg muscles for running, climbing, and jumping, just like ordinary squirrels. The wings give them only a small added advantage over their Muggle

cousins, no more."

Hermione half-raised her hand, then pointed at the cage. "What will happen to that squirrel, Professor?"

Snape exchanged glances with Professor Grubbly-Plank. "My colleagues and I shall study it, Miss Granger. We shall attempt to learn as much about it and its habits, strengths, and weaknesses, before the horde descends upon the Forbidden Forest."

"Horde!" Pansy's shriek rose by at least an octave.

"Forbidden Forest?" asked Harry.

Snape inclined his head. "Indeed, Potter. Regardless of the countryside through which they passed during their migrations, the Fatal Squirrels always prefer a wooded area to open grassland. Undoubtedly, they will be attracted to the Forest, not only for the trees, but also by its strong Magical aura. Numerous warm-blooded creatures – some Magical, some not – reside here. In any case, due to last spring's late freeze – not to mention the summer's drought – we have a vastly-reduced supply of nuts on the trees this autumn, and the squirrels will be looking for other sources of sustenance. I would advise everyone to stay well away from the edge of the trees."

His eyes narrowed dangerously. "It goes without saying that – as always – entering the Forbidden Forest is strictly prohibited." The man's black eyes glared in turn at each of three particular Gryffindors, before he added, "If you should spot a Fatal Squirrel while you are out upon the grounds, do not attempt to approach it."

Ron muttered, "Is he trying to make a joke?"

"Run immediately for the castle, and remember – Aguamenti." Again, Snape's wand spurted water, wetting down the toes of Ron's trainers.

"Bloody hell!" The redhead jerked his feet back underneath his bench as the Potions Master smirked.

"Twenty points from Gryffindor for language, Weasley."

The man's black robes twirled through the dust as Snape spun around to face the class as a whole. "Questions?"

"How many Fatal Squirrels are coming, Professor?"

"Unknown, Mr. Zabini. We'll have to wait until they begin arriving before we can estimate accurate totals. Expect several hundred at the very least … and possibly several thousand."

Pansy covered her face with her hands and moaned something that sounded like, "Merlin, Merlin, Merlin…"

"What about Hogsmeade weekends?" Draco asked.

Snape shook his head. "Suspended until further notice, Mr. Malfoy. We cannot risk anyone being attacked walking to and from the village."

Harry raised his hand.

"Potter?"

"How will we get updates on information regarding the Fatal Squirrels, sir?"

"Announcements will be made at mealtimes in the Great Hall. The same information will be posted daily in common rooms. As we learn, we shall pass known facts on to the student body, for their own safety." He paused, then added, "Ordinarily, I should refrain from passing on items involving mere speculation. However … since we still know relatively little about these Fatal Squirrels, the Hogwarts staff may decide to offer ideas which are based on LOGICAL deduction. Whenever that may be the case, we shall make it very clear that we are speculating and that the information has not yet been proven to be factual."

Snape grimaced. "I imagine, given the fiasco involving the Fatal Squirrels in Diagon Alley, that the Daily Prophet will be rife with unproven rumors and wild speculation. Do bear in mind that the so-called journalism appearing in the Prophet very seldom encompasses LOGICAL deduction."

The students laughed aloud.

"Any further questions?"

Silence.

"Professor Grubbly-Plank…" Snape ceded his position as guest lecturer.

The gray-haired CMC professor stood, brushing off her robes. "Thank you, Professor Snape. Chapter Three in your textbooks for next time. Class dismissed."

Although Harry and his friends – not to mention at least a third of the class – would have liked a closer look at the Fatal Squirrel, Snape had already gently lowered the cover over the cage before they could approach.

Ron nudged Harry's ribs with his elbow. "You notice how he's so much nicer to that squirrel than he is to us students?"

Harry shrugged, taking up his school bag. "Oh, I don't know, Ron. He really wouldn't want to antagonize it, especially when he needs to study it. Besides, Snape wasn't so bad today. Not as bad as usual, you know?"

"That's what worries, me," said Hermione as they began trudging back up the steep path to the castle. "If Snape loses his … snark … over the Fatal Squirrels, then they must pose an extremely serious threat." She shook her head, bushy hair bouncing. "I'll bet it's only a matter of time before they kill someone."

-:- -:- -:-

Over the next month, most of the Hogwarts staff put their heads together and collaborated on studying and running experiments involving the Fatal Squirrel residing in Hagrid's hut.

Certain teachers, however, did not take part. Dolores Umbridge felt that the task was far beneath her and best left to lesser witches and wizards. Sybill Trelawney refused to leave her tower, saying surely she must be in the only safe place in the entire castle – the Fatal Squirrels could never fly that high, and as long as she kept her ladder drawn up, they couldn't climb…

As caretaker, Argus Filch, was exempted, as he had nothing useful to contribute, although he offered an endless running commentary to the effect that it was bad enough having to clean up after students, and he hoped to Merlin he'd never have to clean up after a pack of bloody vampire-squirrels. To top it off, Filch had taken to wearing Mrs. Norris draped over his shoulder as he patrolled the corridors; the news that a Fatal Squirrel could kill a small mammal had him brandishing his push-broom at every other shadow.

Snape absolutely refused to allow students near the caged Fatal Squirrel; however, Harry, Ron, and Hermione had discovered that Professor Grubbly-Plank proved more welcoming, and they took to visiting the hut when Snape was teaching a Seventh Year Double-Potions class each Thursday. Sadly, in mid-October, Hagrid's chimney still showed no sign of smoke, but they resolutely trekked down the steep path to get the latest update on the Fatal Squirrel from their substitute CMC teacher. While the announcements in the Great Hall and on bulletin boards concerned basics about what was known and suggestions for students concerning defending themselves, the three Gryffindors knew that Professor Grubbly-Plank would discuss some of the actual experiments with them, giving them a slight edge over the rest of the student body.

"Can you imagine," Harry said, interrupting himself long enough to pop a peanut into his mouth, chewing as he negotiated the path, "if Hagrid were in charge of a Fatal Squirrel?"

"Harry!" squealed Hermione. "Don't even THINK such a thing!"

"No kidding mate," agreed Ron, grabbing the packet of peanuts dangling from Harry's hand. "As if a baby dragon wasn't bad enough!" He poured out a handful of peanuts and crammed them into his mouth. "A Fmmff Sqrrmmph omphf vrrmmf…"

Harry snatched his remaining peanuts away from Ron. "You wouldn't care to repeat that after you swallow, would you?"

After crunching the nuts into jagged fragments not quite large enough to choke him, Ron swallowed painfully several times, coughed slightly, and repeated, "I said, a Fatal Squirrel would be the worst! Hagrid would probably let it out of its cage for some fresh air and exercise, and it would make a beeline for the Forbidden Forest."

Hermione nodded grimly. "I love Hagrid – we all do – but he lacks good judgment when it comes to dangerous creatures."

"Lacks common sense, too," muttered Harry. "Just because he's bigger than average doesn't make him immune to danger. A Fatal Squirrel might not be able to kill him single-handedly, but it could still seriously injure him. I guess it's just as well he's still away, but I wonder where he is?"

Ron shrugged. "Well, Dumbledore and the other teachers aren't saying, but we'll pump Hagrid when he finally shows up. You know he'll never be able to keep a secret!"

"Who knows," sighed Hermione. "It might not even be top-secret – just something the teachers feel doesn't concern students, and that's why they're not telling."

They'd arrived at the hut's doorstep. Harry raised his hand to knock upon the open door.

"Come in, children," called Professor Grubbly-Plank.

The Gryffindors winced at the word "children" – they were Fifth Years, after all. In fact, Hermione had just turned sixteen.

"Good afternoon, Professor," greeted Harry, stepping over the rough doorsill. "How is the squirrel getting along?"

"About as usual, Potter," she replied, heating Hagrid's large kettle with a quick Charm. As she laid out cups and saucers – her personal regular-sized set, instead of Hagrid's soup-bowl sized cups – the Gryffindors slowly approached the large enclosure set against the back wall, from which Hagrid's huge bed had temporarily been relocated to the castle.

In place of the original smaller cage, the Fatal Squirrel now lived in a sizeable area where it had more room to move around. The floor was now grass covered, and Hagrid's ceiling had been enchanted like that of the Great Hall to allow the squirrel to experience sunlight and darkness, instead of living in the perpetual candlelit gloom of the hut. Two smallish trees stretching up to the sunny ceiling gave the animal a place to climb and perch. Or to hang and swing, the students were started to discover. The Fatal Squirrel dangled upside down from a thin limb, front paws drawn tightly against its pale green chest.

"Does he do that often?" Hermione asked. "Sleep upside down, like a bat?"

"She," corrected Grubbly-Plank, "apparently has a set of retractable claws on the back of her heels. I've never seen anything like it." She shook her head. "It makes me wonder if there might not be a third type of creature crossed into the squirrel/bat scenario."

"Wow!" breathed Ron, watching the Fatal Squirrel gently swinging by her heels. "That's … amazing."

Professor Grubbly-Plank snorted. "It only makes it more difficult to get a grasp of the animal's true nature."

"But it hangs like a bat because it's part bat?" guessed Harry.

"Presumably, that would be the root of her inclination," agreed the professor. "Although, she doesn't actually sleep upside down. For sleeping, she built that nest." The woman pointed to a rough bundle of leafy twigs which had been woven into a typical squirrel-type nest high up in the left-hand tree. "We charmed the tree to keep replacing the twigs she harvested so she'd have sufficient building material."

"What else have you learned, Professor?" asked Hermione. "We really haven't heard a lot in the castle, despite Professor Snape saying announcements would be made. Aside from suggestions for how to defend ourselves, there hasn't been a lot of information coming our way."

The CMC professor gestured for the students to join her at the table for tea. "Honestly, we don't know that much more than we did a month ago. It's a shame we can't study the Fatal Squirrel in the wild, because we'd obviously learn far more, but that is simply out of the question." The woman poured out tea and passed a plate of shortbread wedges. "We have learned that, in addition to most types of nuts, the animal will eat dried maize, and also seems fond of catching moths to eat at night. She refuses all types of fruits except raisins and pineapple, but she adores sunflower seeds, Brussels sprouts, shiitake mushrooms, dandelion greens, and marshmallows."

The students chuckled at the idea of a greenish-gray vampire-squirrel eating puffy marshmallows.

Professor Grubbly-Plank shook her head. "In the wild, an ordinary squirrel would eat a wide variety of plant foods – various wild greens and field mushrooms, for example – and if a garden is handy, it may even raid vegetables, leaving its mark upon various members of the cabbage family, cucumbers, green beans, cherry tomatoes, and various types of squashes. It will also indulge in nibbling pinecones and certain types of flowers, such as carnations and chrysanthemums. Regular squirrels – whether wild or captive – also love many types of fruits, both native and tropical."

"Wow!" said Ron. "They sound like regular pigs!"

Harry heard Hermione mutter something that seriously sounded like, "You should know…"

"Also, she willingly eats earthworms if given them, but she will not dig them from the ground."

"That's WEIRD," commented Ron.

Harry frowned. "I didn't know squirrels ate fruit, but I thought bats would."

The professor shrugged and sipped her tea. "It really depends on the type of bat, Potter. And even if ordinary squirrels do eat certain types of fruits, this poor creature probably exhibits a grossly-restricted diet, which includes highly-atypical tastes, simply because of the dastardly hybrid genetics in her background. There's a reason that Magical crossbreeding is illegal – you can't predict what the end result will be, much less how adversely the creature itself will be affected. You can't count on getting the best of both worlds."

"What about blood?" wondered Ron. "How do you test that? Put it out in a bowl like earthworms?"

Professor Grubbly-Plank looked pointedly at the teapot and the shortbread. "Are you certain you'd want to hear the details while you're eating?"

The Gryffindors stared at each other.

"Well," ventured Harry, "this is really the only time we can come. And Professor Snape will be out of class before long, so you'd best tell us now."

His friends nodded agreement, although their expressions revealed trepidation.

"Very well," said Grubbly-Plank, setting her teacup in its saucer. She patted her lips with a napkin, took the time to light her pipe, and leaned back in her chair.

"All of the experiments we've done have been non-invasive on the part of the Fatal Squirrel. We simply observe behavior under various conditions. As long as the animal is well fed on nuts and other non-meat sources, it will ignore living creatures. We introduced small animals – like mice, rabbits, hamsters, a Niffler, and a Welsh Conebagger – into the enclosure."

"What's a Welsh Conebagger?" asked Harry. He half expected for Hermione to supply the answer, but his friend looked as puzzled as he did.

Grubbly-Plank answered, "It's a Magical creature barely larger than a rabbit. It's a marsupial which lives on pine nuts and is quite fond of collecting them and carrying them in its pouch to store at home in a hollow tree. On occasion, the Conebagger has been known to shove an entire pinecone into its pouch. Thus, its name. A Conebagger's digestive tract secretes an enzyme which interacts with the pine nuts, rendering the animal's droppings to possess soporific qualities."

"Soapy?" asked Ron.

"Oh, no!" squeaked Hermione. "I just remembered. I saw it in 'Moste Potente Potions' in Second Year! Powdered Conebagger Scat – it's used in Sleep-Eze Potion! Animal droppings!"

Harry's eyes bugged. "That's – Is that the same as Dreamless Sleep?" How many times had he taken THAT?!

Hermione suddenly blushed, looking unaccountably guilty about something, but she shook her head reassuringly, saying, "No, it's just an ordinary, though powerful, sleeping draught."

Harry blew out his breath in relief.

"Soapy?" repeated Ron. "Soapy qualities?"

"Soporific, Ronald," huffed Hermione. "They make you sleepy, not soapy!"

"But what if you wanted to sleep in the bathtub – "

Harry cut in, "What happened with the animal experiments, Professor? The rabbits and such?"

Grubbly-Plank glanced at the Fatal Squirrel's enclosure. "We believe that Fatal Squirrels may possess a faster metabolism than ordinary squirrels, which – if necessary – can go several days without food. As long as this Fatal Squirrel had plenty of plant-based foods, she ignored the animals, but when we withheld plant-based foods completely for more than twenty-four hours, she would attack the other animals in the enclosure with her."

"Oh, no!" gasped Hermione. "That poor Niffler! They're so sweet. Did it … did they…?"

The CMC professor sighed sadly. "The Fatal Squirrel went for the Magical creatures first, beginning with the Conebagger. She ripped its throat and drank the blood for immediate satiation, and when no plant foods proved forthcoming in the next six hours, she eventually consumed its flesh."

"And the Niffler?" Harry asked with dread.

"We kept close watch after the Conebagger incident. The squirrel had stuffed herself on meat and slept for two full days afterward."

"Because of the soporific aspect?" inquired Hermione, curious in spite of her revulsion.

"Excellent question, Miss Granger, but we have been unable to determine the answer to that. It may simply be that the squirrel had overeaten to the extent that she needed to 'sleep it off' while her system digested the Conebagger."

Something occurred to Harry. "Did you test the Fatal Squirrel's droppings?"

Professor Grubbly-Plank laughed aloud, exhaling a burst of fragrant smoke. "Spoken like a true scientist, Potter! Professor Snape has taken charge of the squirrel's droppings. I imagine he's running every possible test he can think of, but I don't yet have any results to report."

"And the Niffler?" He returned to his earlier question. "What happened?"

"When the Fatal Squirrel awakened, she searched the enclosure for plant-based foods, and when she could find none, she launched herself at the Niffler."

"No…" Hermione moaned.

"Like I said, we were monitoring very closely, and we rescued the Niffler – literally conjured it out of the enclosure before the Fatal Squirrel could do more than land upon it. The Niffler was terrified, but uninjured."

"Don't tell Hagrid!" Ron warned. "He'd never forgive you for endangering a cute little Niffler."

Grubbly-Plank shrugged. "I understand your sentiments, Mr. Weasley, but we had to know. And that experiment seemed to bear out the idea that Fatal Squirrels are drawn to attack Magical creatures over non-Magical, when the choice exists. Only after the Conebagger was killed and the Niffler was removed, did the squirrel attack, drink, kill, and eat one of the rabbits."

Tears formed in Hermione's eyes. "Poor little bunny…"

"Once we resumed feeding nuts, maize, sprouts, etc., the Fatal Squirrel ignored the remaining animals – until several days later, when we withheld plant foods once again. This time, with no Magical animals in the enclosure, the squirrel did not hesitate to attack the remaining rabbit."

"That's so sad," said Hermione. "So very, very sad."

The professor reached over and laid a sympathetic hand on the girl's arm. "Yes, it is. But without any other way to learn about the Fatal Squirrel, it was necessary."

"Have you discovered any weaknesses?" asked Harry. "Or any means to stop it from attacking?"

Grubbly-Plank drew contemplatively upon her pipe. "We've tried various non-lethal Charms, Hexes, Jinxes, Spells, and Curses, but the Fatal Squirrel seems fairly oblivious to them all." She shook her head in puzzled frustration. "We're assuming that whatever Magic went into their creation also works to render the animals impervious to Magical intervention. Professor Dumbledore reports that Ministry officials were forced to resort to using Avada Kedavra to destroy the squirrels captured in Diagon Alley. But indiscriminate use of an Unforgivable is out of the question, particularly here at Hogwarts. We're still attempting to devise some effective means of repelling the creatures, but so far, we have only duplicated the Goblins' solution of spraying the Fatal Squirrel with ordinary water. For some unknown reason, the animal cannot function well when soaking wet."

"What about regular squirrels?" asked Harry.

"Not as much of a problem for them, although they'd prefer to be under cover during a bad storm. Even ordinary squirrels, when soaked, can quickly take a chill, which may prove fatal. No pun intended," the elderly witch added with a wry smile.

"Weird," said Ron. "So, we're still supposed to use Aguamenti if they come at us?"

"Yes," said Grubbly-Plank. "Water is our main weapon, believe it or not. We've experimented in a large outdoor enclosure, and we've found that the squirrel's wings absolutely do not function to fly or glide when wet. The Fatal Squirrel is earthbound when wet to the skin. It even experiences difficulty climbing trees when wet, which is not typical of ordinary squirrels."

"So," said Harry, "squirt them with water, and they can't fly, glide, or climb easily. And being wet also slows their running along the ground? I think that's what I remember from Professor Snape's lecture that day?"

"Yes," confirmed the CMC professor. "Aguamenti is the only effective Charm we've found to use against the Fatal Squirrel."

Harry got up and walked over to the Fatal Squirrel's wire mesh enclosure. "Aren't you a mystery?" he said under his breath, watching the squirrel, who had swung upright, then climbed to perch on a higher tree branch. Near Harry's feet, a hamster scurried by. The Fatal Squirrel seemed to be watching its progress along the grassy floor. Not wanting to witness a violent, bloody death, Harry called to Professor Grubbly-Plank, "Is it okay if I feed her some peanuts?"

"By all means, Mr. Potter. She's quite fond of them. Just don't get attached to her, and do NOT even think of giving her a name."

"Right." Harry dug into his pocket and pulled out his half-empty packet of peanuts. "Here you go," he called softly to the verdigris squirrel. He poised the peanut in an opening of the wire mesh. The squirrel's bat-ears twitched visibly. She was no longer watching the hamster. Harry flipped the peanut into the enclosure and was treated to the startling sight of the leathery wings suddenly spreading wide, before the Fatal Squirrel glided gracefully down from near the twelve-foot-high-apex of Hagrid's ceiling.

The squirrel's wings quickly contracted into stick-like appendages as she bounced across the grass in typical squirrel fashion. Harry smiled sadly as she approached the peanut. Based on Professor Grubbly-Plank's warning, he surmised that this Fatal Squirrel would eventually have to be destroyed. It was the least he could do to give her a few treats during what remained of her short life. Especially after the poor creature had been hit by so many magical hexes. Even if she appeared unaffected, it still couldn't have been a pleasant experience, and possibly quite frightening. By "non-invasive", it seemed like Grubbly-Plank meant that their experiments had merely excluded vivisection and other equally-grisly surgical procedures.

The Fatal Squirrel's bushy verdigris tail twitched appreciatively as she sniffed at the roasted peanut. Eagerly, she reached out with both front paws to grasp the peanut…

The creature emitted a high-pitched, rasping screech, which Harry could only interpret as a shriek of severe pain. The Fatal Squirrel dropped the peanut from her smoking paws, screeching in obvious agony. Instinctively, she attempted to soothe away the pain by licking the pads of her paws, only to scream even louder as a trickle of pale smoke seemed emanate from her mouth.

Harry stumbled back from the enclosure, even as Grubbly-Plank leaped from her chair and rushed toward him, shouting, "Potter, what did you DO? What did you DO to that poor creature?"

"WHAT is going on in here?" demanded a stern voice, as the doorway darkened ominously.

Snape, thought Harry. Just my luck. And, of COURSE he'd come at the worst possible moment…

"Potter, what did you DO?" repeated Grubbly-Plank, grabbing Harry by both biceps while she stared at the squirrel, who had desperately leaped into a shallow puddle intended as drinking water for the animals in the enclosure. The suffering animal gulped water while holding her front paws deep in the cooling liquid.

To Harry, it appeared that the squirrel was intent upon relieving the pain of a sudden burn.

"I – I didn't do anything, Professor," he stammered. "I just tossed her a peanut… She grabbed it, then screeched, and it looked like smoke was coming off her paws … then her tongue…"

"Smoke?" Snape had plowed past Ron and Hermione, and now he alternated between glaring at Harry and staring at the Fatal Squirrel, who was tenderly licking the flesh of her wet front paws as she sat upright in the middle of the puddle. Even from this distance, her skin appeared damaged.

Harry nodded. "Yes, sir. Smoke. Almost like her paws had caught fire…"

Snape silently whipped his wand in several quick patterns, and the Fatal Squirrel suddenly found herself encased in a sturdy protective sleeve, with her head completely covered, except for a breathable stiff mesh to allow air to penetrate. Another wave of his wand conjured the animal, sleeve and all, from the enclosure into his hand. The stiffness of the sleeve prevented the animal from maneuvering, attacking, or getting away, and while she was gently incapacitated, Snape and Grubbly-Plank carefully examined her front paws.

"Burned," announced Grubbly-Plank. "Without a doubt. Second-degree blisters, and a couple of areas of third-degree blackened flesh."

Hermione, peering over the CMC professor's shoulder, appeared sickened.

"Potter, I'll ask you once more: WHAT. DID. YOU. DO?" Grubbly-Plank demanded fiercely.

"I just tossed her a peanut, Professor! That's all."

"Accio peanut!" Snape didn't even bother with his wand. He simply pointed a pale finger and caught the peanut after it whizzed through the mesh of the enclosure. He examined it carefully, then held it out to Grubbly-Plank. "Notice anything?"

She took the peanut, turned it this way and that, rubbing it between her fingers… "Potter, this isn't one of my peanuts. Mine are raw. This one has been roasted. Where did you get it?"

Harry held out his packet. "I brought them down from the castle. Actually, I brought several packets to school with me in my trunk. I bought them last summer in a Muggle store…"

Snape and Grubbly-Plank examined the printing on the heavy plastic wrapper, which proudly advertised its contents as "Salted Peanuts".

"Merciful Merlin! That's it! That's IT!" gasped Grubbly-Plank.

"What's it?" asked Harry, somewhat shakily.

"Salt, Potter," said Snape in his best Addressing-the-Dunderheads voice. "I believe you may have given us our first major break in formulating a defense against the Fatal Squirrels."

The Gryffindors stared at the dark Potions Master, wide-eyed.

"I don't understand, Professor," admitted Harry. "Salt? How? Why?"

Snape sneered at the boy before speculatively regarding the squirrel in his hand. The creature's eyes were just fading from agitated electric blue to a more normal dark, almost-purple, blue. "I could give an entire lecture on the history of salt and its uses in purification from evil, as well as its employment in fighting against Dark Magic and other Dark forces, including human vampires. Suffice to say that, upon contact, salt – ordinary table salt – apparently causes severe burns to the flesh of the Fatal Squirrel. At long last, we may be able to devise a form of squirrel repellent and possibly a means to weaponize it."

"But Professor," inserted Hermione, "Isn't there salt in blood? And the Fatal Squirrels drink blood. Sometimes."

"Astute observation," agreed Grubbly-Plank before Snape could do more than glare at The-Girl-Who-Still-Believed-She-Knew-It-All. "However, if the squirrels are capable of drinking blood without suffering adverse effects, obviously it requires a far higher concentration to inflict physical harm. A stronger solution, or direct contact with a granulated form of the chemical."

"Chemical?" wondered Ron.

Snape turned his dark sneer in the redhead's direction. "Sodium chloride, Weasley."

The boy shrugged slightly, still frowning in puzzlement, causing Hermione to hide a smile, but Harry grinned openly at her behind Ron's back. It would appear that Wizarding home-schooling didn't always bother with certain aspects of science.

Professor Grubbly-Plank was waving the tip of her wand in tightly-controlled small circles above the Fatal Squirrel's paws, and the blistered, blackened flesh slowly resumed a more normal appearance. Using further magic to open the squirrel's mouth without risking being bitten, the CMC professor successfully healed the animal's swollen tongue and lips. "Give her a day to recover from the trauma," she advised Snape, "and we can begin running salt-based tests."

"Indeed." Snape waved his wand to return the Fatal Squirrel to her enclosure, Vanishing the protective sleeve once she was safely contained by the wire wall.

The teachers and students watched as the squirrel flapped her leathery wings and flew jerkily up to the highest tree limb in the enclosure. Once safe upon her perch, she leaned forward and rasped a scolding at the humans. Even from that distance, they could clearly see that her eyes had returned to electric blue as her body jerked angrily.

"Day after tomorrow," said Snape, narrowing his own dark eyes at the Fatal Squirrel. "First thing in the morning."

"Poor thing," whispered Hermione, feeling her stomach clench in dread for the squirrel.