The strange footsteps stopped outside the door.
There was no knock.
The oak door of the living room, that door which had once blocked countless clients, police officers, and even desperate fugitives, was now being slowly pushed open by an invisible hand.
The motion of it opening was exceptionally smooth; the hinges did not emit the slightest creak or groan, as if it were not a heavy wooden door being opened, but a weightless curtain.
A figure elegantly and silently embedded itself into the doorframe.
The air in the room seemed to be sucked away in an instant; the flames in the fireplace suddenly dipped, emitting an uneasy crackling sound.
Dr. Watson felt his throat tighten, his fingers gripping the coffee cup subconsciously, the cold porcelain transmitting a chill.
The visitor stepped out from the shadows and into the reach of the light.
He was tall and straight, almost matching Holmes in stature, holding a black cane and wearing an impeccably tailored dark three-piece suit.
The material of the suit was quite peculiar; under the dim light, it presented a nearly liquid, deep black, absorbing all the light it touched. Looking closely, it seemed as if extremely faint, starry fluorescence was flowing deep within its texture.
He wore a bowler hat of the same color, the shadow of the brim perfectly obscuring the upper half of his face, revealing a slightly thin countenance.
What was most striking was his skin tone, a pure, dark color like polished ebony, shimmering with a healthy and restrained luster in the dim light.
His gait carried a strange elegance; every step seemed to have been precisely measured in distance, landing silently, yet carrying a heavy sense of presence.
He walked to the center of the room and stopped a few paces away from Holmes and Watson, his posture as composed as if he were the master of this house.
He nodded slightly and removed the bowler hat from his head.
"Good evening, Mr. Holmes, Mr. Watson."
His voice sounded, low and mellow, like aged wine flowing over silk, carrying a nearly perfect British accent, yet at some extremely subtle tonal inflection, it revealed a hint of an indescribable, alien quality.
"Please forgive my presumptuous visit; I am Nefren Ka."
When he announced his name, a subtle, elusive smile appeared at the corners of his mouth, as if the name itself were the beginning of a carefully designed puzzle.
Holmes did not respond immediately.
His gaze had been locked onto Nefren Ka the moment he stepped into the room, beginning that famous "deduction method" scan.
Those sharp gray eyes began from the hat on his head and moved downward with dazzling speed, capturing every possible detail.
Nefren Ka placed the removed bowler hat casually on the corner of Holmes's table, which was piled with experimental instruments, his movement so natural it was as if that were where he habitually placed his hat. His gloved hand then proceeded to unbutton a button on his suit jacket, the movement fluid and relaxed.
Holmes's pupils contracted slightly; on the metallic cufflinks, an unknown, bizarre rune was etched. His gaze lingered for a moment, and he felt as if his consciousness would be twisted and sucked into it.
"Please sit, Mr. Nefren."
Holmes finally spoke, his voice returning to its usual calmness, but deep within, a high degree of excitement was hidden.
He made a concise gesture pointing to the empty chair next to Watson's armchair, while he himself slid silently to the side of the fireplace, leaning against the mantelpiece, his fingertips lightly pressed together, assuming his usual posture for thought.
His gaze remained glued to Nefren Ka as if it were tangible, not missing a single subtle movement.
"Thank you for your generosity."
Nefren Ka smiled slightly, the smile like ripples on water, elegant yet lacking warmth. He walked toward the chair without the slightest hesitation in his steps.
The moment he sat down, as if receiving a command, the torrent of deduction instantly poured out from Holmes, his speech fast and clear, carrying unquestionable confidence.
"Mr. Nefren, from the very first step you took into this room, you have been telling a fascinating story."
"Your cane." Holmes's gaze sharply swept over the cane Nefren Ka had leaned against the table—a cane that was jet-black, with a strange gemstone embedded in the head.
"The tiny traces of wear on the top, as well as the habitual position where you hold it, indicate that you are accustomed to long-distance, fast walking, and that you are accustomed to thinking while walking, with your center of gravity leaning slightly forward."
"Your destinations often require traversing complex urban terrain, or you are rushing under time pressure."
"London? No, the soil particles adhering to the bottom of your cane," Holmes's nostrils flared almost imperceptibly, "carry a unique mineral composition and trace amounts of pollen spores that do not belong to any known local vegetation."
"Combined with the extremely subtle way the edges of your trouser cuffs are worn—those are special scratches caused by frequently passing through low shrubs—I deduce that you have recently returned from overseas, from a tropical or subtropical region with lush vegetation and ancient, complex geological structures. Africa? The depths of the South American jungles?"
The elegant, seemingly eternal smile on Nefren Ka's face deepened. He neither nodded nor shook his head, but just listened quietly, stardust seemingly flickering in his deep eyes.
"Your attire, impeccable Savile Row bespoke, but the details are intriguing."
Holmes spoke even faster, his gaze sweeping once again over Nefren Ka's open suit jacket, the buttons exuding a strange matte finish under the light.
"The material of the buttons is not a common alloy, but a type of... metal I cannot precisely identify for the moment."
"This material, along with those mysterious patterns on your cufflinks, suggests that you have close ties to certain frontier fields that may involve metallurgy or materials science, or that you serve some organization with extremely high requirements for confidentiality."
Holmes's gaze locked onto a small segment of a watch chain visible at the edge of Nefren Ka's waistcoat pocket; the chain links were as fine as the scales of some creature, the material equally peculiar.
"Your pocket watch chain—the degree of wear does not match the habits you reveal when using it; it appears too 'new'. This chain is new, yet your habit of wearing the pocket watch is fluid and natural. This means you only recently replaced it, and the material of the replaced chain is not an ordinary object."
Holmes's gaze, carrying an invisible pressure, fell upon the black-gloved hands Nefren Ka had placed on his knees: "And your hands, Mr. Nefren Ka."
He leaned forward, his sharp gaze like a scalpel, attempting to cut through Nefren Ka's perfect facade and reach the core.
"You are wearing gloves, which in itself speaks volumes. What are you trying to cover up? Some kind of professional trace? Scars? Or..."
Holmes took a deep breath, his deduction like a speeding train heading toward the final platform: "In summary, Mr. Nefren: You are a professional who has long been engaged in covert work overseas, likely employed by a government or a large multinational organization, with tasks involving frontier technology or highly confidential geographical exploration."
"You recently returned to London from some tropical region with a special geological environment and dense vegetation."
"Your awareness of keeping your own identity confidential is extremely strong, to the point that you would even replace items you have worn daily for years. The gloves on your hands are perhaps proof of your professional risks, or perhaps they point to a deeper secret of yours, or perhaps it is merely caution."
He paused, his gray eyes staring intently at Nefren Ka.
"So, Mr. Nefren, you have traveled across half the globe, bringing so many mysteries to find me, Sherlock Holmes. What is your purpose? Is it to unravel your own secrets, or have you brought a... challenge worthy of my involvement?"
Holmes finished speaking fluidly, his body leaning forward even more, his fingertips habitually pressed together, resting beneath his jaw.
Those eyes burning with the flame of inquiry stared intently at Nefren Ka, capturing the slightest muscle twitch on the other's face, any trace that could confirm or overturn his deductions.
This was the weapon he prided himself on—the deduction method. He was like a swordsman with peak skills, confident that this strike had already pierced the mist of appearances and reached the core.
Watson held his breath, his gaze shifting nervously between Holmes and the visitor.
Silence enveloped the room, with only the occasional crackling and popping sound of firewood burning in the fireplace, as if unable to bear a heavy burden, echoing in the room.
Then, Nefren Ka smiled.
The smile initially rippled only extremely subtly at the corners of his mouth, like ripples caused by a pebble thrown into a deep pool, spreading silently and slowly.
It was not mockery, but a kind of pleasure—a pure, deep pleasure, as if he had insight into some huge joke in the universe.
The smile finally reached his eyes, those deep eyes that were revealed after the shadow of the hat brim faded. At this moment, they flickered with an indescribable light, neither joy nor contempt, but more like a nebula silently rotating and collapsing in the distant void.
"Ah, Sherlock Holmes."
His voice remained low and pleasant, but that hint of an alien quality now became clearly discernible, like a note belonging to no known instrument mixed into a perfect musical movement.
"The beacon of London, the embodiment of logic, the peak of deduction that the human mind can reach... truly worthy of your reputation."
He elegantly spread his empty left hand, palm upward, his posture as composed as if he were displaying a rare treasure.
"Your capture of details is breathtaking—the wear on the cane, the adhering soil particles, the clothing material, even the analysis of personal habits. This insight, among humans, is indeed rarely matched."
He leaned forward slightly, those deep eyes that seemed capable of containing the entire universe staring directly at Holmes, carrying an indescribable sense of oppression.
"However," he changed the subject, that hint of a smile suddenly deepening, becoming as unfathomable as an abyss, "you use the bricks and stones of the known world, attempting to build a staircase to a wall leading to the unknown. Unfortunately, this wall is... much, much higher than you can imagine."
His gaze swept over Holmes's tense face, then passed over Watson's face, which was full of confusion and vigilance, and finally fell back onto his own spread left hand.
"An agent performing covert work? An interesting model that conforms to the logic of the human world, a delicate shell."
"Unfortunately," he shook his head gently, "the 'facts' you observed, their roots are far beyond the soil you are familiar with. You have seen the 'effect', but you cannot reach the completely strange 'cause' that gave birth to it."
The moment his voice fell, Nefren Ka's right hand, wearing a glove of the same color as his suit, reached extremely naturally toward the inside pocket of his suit jacket.
Watson's nerves tightened to the limit instantly, his muscles contracting subconsciously, almost making a defensive move. This position was too easy to conceal a weapon!
The sharp light in Holmes's gray eyes also suddenly condensed, his entire body's senses heightened to the limit, capturing every subtle angle of the other's fingers, the trajectory of the slightest twitch of his arm muscles.
The air seemed to solidify into heavy lead, the crackling sound of the fireplace flames suddenly amplified, like some kind of ominous countdown.
The black-gloved hand slowly withdrew from the deep pocket.