[From the journal of Captain Arthur Hastings]
A strange sort of melancholy had settled over our party in the wake of the affair at the Velvet Rabbit. Holmes had his clue—the bizarre symbols traced in the carpet—but it was a clue from a language we did not speak, a signpost pointing the way into a deeper and more terrifying wilderness. The investigation felt less like a hunt and more like a descent, each new discovery pulling us further down into a world that operated on a logic entirely alien to our own.
It was in this contemplative mood that I found myself one evening taking a walk with Hercule Poirot through a small, quiet park near our hotel. The frantic, neon-lit energy of Tokyo was muted here, replaced by the gentle rustle of leaves and the soft glow of paper lanterns. For a time, we walked in a companionable silence.
"It is the chaos of it all that vexes me, Hastings," Poirot said at last, his voice a low, troubled murmur. He stopped and stared at the reflection of the moon in a small, placid pond. "My whole life, my entire method, it is built upon the foundation of order. A crime is a disruption of the natural order. The clues are the pieces of that disruption. One gathers the pieces, exercises the little grey cells, and puts the order back. Voila. It is simple. It is elegant."
He turned to me, his brow furrowed with a profound, intellectual frustration. "But this… this is not a disruption of order. It is a new order being created by a madman. Or perhaps, two madmen. We have Kira, the puritan. His work is clean, precise, almost surgical. He passes judgment like a god on a mountain, and his victims simply… cease to be. There is a terrifying logic to him. He is a fanatic, but a fanatic of order."
"And B.B.?" I prompted.
A look of genuine distaste crossed my friend's face. "Ah, B.B.," he sighed. "He is the opposite. He is not a god on a mountain; he is a clown in an asylum. He does not seek order; he seeks to create the most extravagant and theatrical chaos possible. His murders are not judgments; they are performances. One seeks to build a perfect world, the other seeks to prove that the world is an irredeemable circus." He shook his head, a gesture of deep weariness. "How can two such opposing forces exist at the same time? How does one find the order in that?"
I had no answer to offer him. Before our conversation could continue, one of the sleek, modern telephones we all carried began to chime. It was Poirot's. A message from L, containing only three words: Return. Urgent. Experiment.
The atmosphere in the hotel suite was electric. The entire team was assembled, their faces grim and expectant. L stood before the main holographic display, beside him, the ever-placid android, Connor.
"We have been granted a unique opportunity," L began, his voice devoid of any preamble. "Through our new American liaisons, we have been given access to a very specific asset. His name is Mateo 'The Ghost' Diaz. He is a former arms dealer, currently held in a high-security military black site in Nevada. His existence is a state secret. His name is known to fewer than ten people on earth, and there is no known photograph of him available to the public."
Holmes leaned forward, his eyes gleaming with interest. "A control subject."
"Precisely," Connor stated, bringing up a dossier on the screen. It showed a man's name, but the picture was a black silhouette. "Mr. Diaz is the perfect bait. Utterly unknown to the world. Kira cannot possibly know of him."
L continued, "At 0800 hours GMT, we will leak his name and a single, never-before-seen photograph onto one specific, heavily monitored dark web forum known to be a gathering place for Kira sympathisers. The subject will be held in a medically monitored cell. He will be conscious and, for the purpose of our experiment, will be given a pen and a pad of paper."
"What is the purpose of the pen, L?" asked Watson, ever the pragmatist.
"We want to observe his final moments," L said, his gaze distant. "Specifically, his motor functions. A heart attack, however sudden, has a physiological progression. We want to see if there is any anomaly in that progression. Any sign of outside influence."
The plan was as audacious as it was grim. They were to dangle a man's life in front of a killer, purely to observe the precise manner of his death.
An hour later, we were all gathered in the darkened suite, the only light coming from the bank of monitors displaying a live feed from the cell in Nevada. The room was a stark, white box. Mateo Diaz, a hard-looking man with a faded tattoo on his neck, sat at a simple table, a pen in his hand, nervously scrawling his name over and over again on a piece of paper. A digital clock in the corner of the screen marked the time.
One of the monitors showed the dark web forum. A user, anonymous, downloaded the file containing Diaz's name and photograph.
"The bait is taken," Connor announced calmly. "If Kira acts as he has before, the subject's death will occur within one minute."
The sixty seconds that followed were the longest of my life. The air was so thick with tension it felt difficult to breathe. We watched the man in the cell. We watched the clock. We watched the medical monitor displaying his vital signs.
At the forty-second mark, it happened.
Diaz froze. A look of confusion, then terror, crossed his face. He gasped and clutched his chest, his body seizing violently. On the vital signs monitor, a frantic, jagged line spiked and then plummeted. A flat, continuous tone echoed softly from the speakers.
"Cardiac arrest confirmed," Watson murmured, his eyes wide with a mixture of clinical fascination and horror. "He is gone."
The man was dead. The experiment, it seemed, was over. But then, something impossible occurred.
On the screen, the dead man's hand, still clutching the pen, began to move.
It was not a post-mortem spasm. It was not a twitch. It was a slow, deliberate, and controlled motion. The pen, held in the grip of a corpse whose heart had stopped beating, whose brain was no longer receiving oxygen, began to write. The silence in our room was absolute, a profound, sacred horror at the sight of a fundamental law of nature being broken before our very eyes.
The dead hand moved across the paper, scrawling four, final, spidery words. The camera feed zoomed in, bringing the message into sharp, terrifying focus.
I SEE A GOD OF DEATH LAUGHING.
The pen fell from the dead man's fingers and clattered onto the table. Watson was speechless, his face pale, his entire medical worldview shattered in an instant. Holmes stared at the screen, his face a mask of cold, hard shock, his mind a furious engine that had finally encountered a fact it could not process.
I turned to Poirot. He was standing very still, his eyes fixed on the impossible message. He had spent a lifetime chasing the evils that men do, confident in the belief that behind every crime was a human mind, a human motive, a human hand. In that moment, watching a dead man write a postcard from the abyss, I saw that certainty crumble.
He turned to me, his eyes filled with a dawning, terrible understanding, a look of such profound dread that it will haunt me to my dying day.
"Mon ami," Hercule Poirot whispered, his voice barely a breath. "My friend… I fear we have been looking for a man, when all this time… we should have been looking for a demon."