Hogwarts: Lacus doesn't want to be a witch who destroys nations.

A cold wind, carrying coal dust and dampness, rubbed against the dilapidated brick walls of London's East End. Holmes tightened the collar of his wool coat, and his brass cane tapped on the wet cobblestones, producing a dull echo.

Beside him, Lux was bundled up tightly, while Lumi, in the wicker basket in her arms, buried her head in the fluffy fur, only her two little hairy ears showing. In Lux's mind, Lumi muttered, "My God, this smell is stronger than the ice cave of the Howling Abyss! It's coal dust, sewers, and... uh, rusty blood? My little nose is suffering!"

"Mr. Holmes, is this the first crime scene?" Lux pointed to the end of a narrow back alley, where rotten vegetable baskets and abandoned wooden barrels were piled up, and the air was filled with a musty, stale smell and a faint fishy odor.

"That's right, the final stop for old baker Henry." Holmes' voice was muffled through his wool scarf. He walked to a wall that had clearly been scrubbed, but dark brown stains still lingered in the cracks between the bricks.

"The body was found here, its chest almost completely ripped apart." He pulled out a notebook covered in black and white photographs.

Lux frowned. The wound certainly didn't look like that of an ordinary wild beast. She drew her wand and whispered, "Reveal your true form!"

As the tip of the staff swept through the air, the dark brown stains on the wall seemed to come alive, instantly emitting a faint, unsettling dark red glow. Extremely fine, black particles, like charred feathers, began to appear in the air, suspended and slowly drifting away.

"Wow! Sis, there's black smoke coming out of the wall!" Lumi exclaimed from inside the basket. "It smells just like when you ruined your potion!"

Holmes immediately leaned closer, his magnifying glass almost touching the wall: "These black particles seem to be repelling light... Miss Lux, what is this?"

"Remnants of dark magic," Lux said gravely. "Very typical traces of magical creature attacks, like... werewolves. Ordinary wild beasts wouldn't leave this kind of 'signature'."

Looking at the drifting particles, she added, "And judging from the concentration and activity, the perpetrator was very strong, or the attack may have occurred not too long ago."

"Werewolf..." Holmes chewed on the word, a glint in his eyes. "It matches the characteristics of the wound and the sense of power. Next, coachman Bill Hopkins."

The second scene was a little further away in a darker alley, near the back door of an abandoned warehouse. The smell was worse there, a mixture of garbage and the stench of some kind of animal excrement. Several deep, unnatural scratches marred the cobblestone pavement.

"The body is here," Holmes said, pointing to a human figure roughly sketched in charcoal on the ground. "The neck is ripped open, almost decapitated, and there is animal hair at the scene." He took out the glass tube containing coarse, silvery-black hair.

Lux waved her wand again: "Reveal your true form!"

This time, not only did a dark red glow emerge from the scratch marks on the ground, but even the air seemed to distort. Under the influence of the spell, black mist instantly rose from the surface of the silver-black fur, even vaguely outlining a blurry, howling wolf head phantom, which vanished in a flash.

"There's another expert." Lux gasped. "This isn't just werewolf fur; it's brimming with powerful dark magic and violent emotions. This werewolf probably just transformed." She subconsciously touched the wand at her waist, feeling a bit uneasy.

Holmes quickly jotted down in his notebook: "Magic carries the emotions of the perpetrator? Interesting. Then, the third one, Emily Green the flower girl."

The third crime scene was right in front of the abandoned warehouse mentioned by Holmes. It was relatively more open, but the warehouse door was rusty and weighed down by heavy iron chains. On the concrete floor in front of the door, there was an even larger patch of dark brown grime.

"This is where Emily was found," Holmes said, his voice tinged with barely perceptible pity. "Her death...was extremely gruesome." He omitted the details but pointed to the stains on the ground. "The fatal wounds were in her abdomen and back, as if she had been repeatedly torn and dragged."

Lux took a deep breath, suppressing the discomfort in her stomach, and raised her wand for the third time: "Reveal your true form!"

This time, the effect was even more astonishing. The stains on the ground not only burst forth with a strong dark red glow, but the magical traces permeating the air instantly boiled over. A pair of huge and twisted claw phantoms covered with coarse hair were frantically tearing apart a transparent humanoid silhouette, accompanied by a silent yet primal and violent roar!

The scene flashed by in an instant, yet it was enough to send chills down one's spine.

Lux instinctively took a step back. "This is pure torture!"

Holmes's face turned ashen, and the magnifying glass in his hand trembled slightly. Even though he was used to murders, this supernatural and maliciously brutal scene still had a huge impact on him.

"The target of his venting... was unarmed civilians. It wasn't hunger, it was pure bloodlust." He closed his notebook, his tone icy. "The chain of evidence is closed. The killer is a werewolf, and a powerful one at that, with extremely unstable emotions."

"Now we need to go to Scotland Yard to see if the body itself can provide more details, especially whether the owner of that hair left a more direct mark on the victim."

Holmes turned to Lux, "Remember, you are my 'scientific assistant,' responsible for recording and analyzing the readings of those 'special instruments.'"

The atmosphere at Scotland Yard was so heavy it seemed like it could be wrung out of water. The shadow of war cast a shadow of exhaustion and anxiety on the faces of every detective. Holmes led Lux ​​through the noisy corridors and headed straight for the morgue area.

The detective in charge of receiving them, Hardwick, was a middle-aged, balding, and shrewd old man with puffy eye bags. He clearly recognized the legendary Sherlock Holmes, but his tone lacked enthusiasm, instead carrying a businesslike perfunctory tone: "Mr. Holmes? Here again? These three cases, the higher-ups said, are classified as wild animal attacks, itinerant crimes, possibly from an illegal circus or some nobleman's private zoo—wild animals that escaped. Everyone's focused on Europe right now, we're short-handed..."

Holmes interrupted him abruptly, his voice carrying an unquestionable authority: "Devik, I know you're under a lot of pressure. The 'peace' that Mr. Chamberlain brought back won't stop the murders in London. The deaths of these three innocent citizens also require the truth. This is my assistant, Miss Lux; she's brought more sophisticated testing equipment."

Hardwick looked suspiciously at Lux, the rattan basket in her arms that kept making a "pop" sound, and the small wooden stick in her hand that looked like a toy.

"Precision equipment? This is it?" he muttered. "Alright, alright, for your sake, you've been pointing fingers here since I was young. Same rules as always, ten minutes. The forensic report is on the table, the body is inside. Look at it yourself, don't touch it, and don't scare the young lady." He pointed to the thin few pages of report on the table next to him.

While Holmes quickly flipped through the vague reports, Lux quietly slipped to the morgue door and peeked inside through the crack. The room was chillingly cold, and three metal beds were covered with white sheets.

Detective Hardwick poured himself a cup of dark, pungent tea and complained to a young officer beside him, "All the higher-ups do is keep pushing, keep pushing, investigating German spies, investigating saboteurs—all the manpower's been diverted to monitoring the docks and factories! Are we supposed to set animal traps in Hyde Park for this kind of wild animal attack? Besides, this awful weather…"

He spat, "It's foggy every day, like living in a coal pile. People are going crazy from suffocation, who cares about wild animals!"

The young officer lowered his voice: "Boss, have you heard? There's a protest in the East District, protesting soaring prices. They're almost unaffordable for bread. And the dockworkers in the South have gone on strike again, complaining about low wages and dangerous work. They're saying there's something unclean in the cargo they're transporting, all weird stuff."

Hardwick waved his hand irritably: "Alright, alright, mind your own business! Let that old Holmes do his thing, and when he's done, he should leave early and not cause us any trouble. He's over eighty years old and he still finds a 'Watson' to play detective games with him."

Holmes closed the report as if he hadn't heard, and nodded to Hardwick: "Thank you, Detective Hardwick. Now let's go in and take a look."

The morgue was chilling. Holmes lifted a corner of the white sheet and examined the wounds with professional and calm movements. Lux, enduring her discomfort, raised her wand and cast "Reveal" again on the corpse's wounds and the werewolf hair in the evidence bag.

From a magical perspective, the remnants of dark magic at the corpse's wound resonated extremely faintly with that single hair.

"Mr. Holmes," Lux leaned closer and said in a voice only the two of them could hear, "the hair and wound residue resonated, indicating a common source, and the corpse had another very faint magical mark, perhaps for tracking?"

Holmes nodded calmly, gesturing for Lux to step back. He carefully examined each corpse, especially places where clues might remain, such as under the fingernails and toenails, but apart from confirming the horrific nature of the wounds and the hair, he found nothing more using Muggle methods.

"Alright, let's go, Miss Lux." Holmes covered her with the white sheet, turned and left the morgue. He ignored Detective Hardwick's perfunctory farewell and led Lux ​​quickly out of Scotland Yard.

The fog outside seemed to have thickened. Holmes stood on the street corner and pulled the London map from the inside pocket of his coat. On the map, he clearly circled the bakery in the East End, Coachman's Lane a little further away, and the spot where the flower girl was murdered in front of the abandoned warehouse with a red pen.

He connected the three red dots.

A near-perfect equilateral triangle appears prominently on a map of East London, its sharp angles pointing directly in a certain direction towards the Thames.

"A triangle..." Holmes muttered to himself, his fingers unconsciously tapping the end of his cane. "Three victims, three locations, precise geometry. This isn't random; is it some kind of ritual? A mark? Or some kind of summoning?"

"A six-pointed star!" Lux blurted out, her mind instantly flashing back to the contents of the Hogwarts History of Wizardry textbook. The past two months of copying had finally paid off.

"Mr. Holmes! In the magical world, the hexagram is a very common basic magic circle. It consists of two overlapping triangles, one equilateral and one inverted."

Holmes stroked his chin: "A six-pointed star, so the killer needs three more points."

Lux patted the wicker basket, making Lumi shudder. The half-eaten biscuit crumb she was holding fell to the hem of her robe. "The hexagram has so many uses in the magical world: summoning, sealing, rituals... Last time I copied a book, it even said that the hexagram could be used as a base for magic circles. This werewolf is using people like elemental stones!"

"Then the next objective is clear." Holmes drew a triangle on it. "Go and examine these three vertices."