The morning Tamagawa was quiet. Five thirty. The early-running course seemed to exist solely for Aizaka Soshin. The promenade heading south from Seta-oka Station still lay in pale twilight. White smoke rising from the factory district across the water was beginning to tint red against the awakening sky. The sound of shoe soles striking pavement. The rhythm of breathing. The pulse of a heartbeat. Soshin heard these sounds while simultaneously capturing everything around him. A sparrow chirped in the thicket ten meters ahead. Behind him, the sound of a bicycle passing over a pedestrian bridge roughly one hundred fifty meters away. Wind direction: northwest. Temperature: approximately sixteen degrees. Humidity in the air. The body of a thirty-eight-year-old man ran with surface indifference. A dull gray jersey. Black running shoes. Short-cropped black hair already streaked with white. Eyes of a grayish, dull brown seemed to gaze forward, yet actually monitored the thicket across the river and the promenade. While running, Soshin always maintained three-hundred-sixty-degree awareness. This was not habit but something closer to instinct. Seven years ago—when he belonged to the Ministry of Defense's unacknowledged special operations unit, "Fourth Action Squad," an extralegal counter-terrorism force whose very existence left no official record—this vigilance had been carved into him. Even changing his quality of life could not erase this caution. Rather, the more he tried to blend into ordinary society, the more this habit became conspicuous. He reached Seta-oka Bridge. The Tamagawa reflected the morning sun, glimmering faintly. Soshin stopped once, placing his hand on the bridge railing. A waterproof, shock-resistant military watch showed five forty-five. While gazing at the river surface, Soshin steadied his breathing. Oxygen circulated through his lungs. An old scar on his scapula ached faintly. The bullet wound scar remaining on his left scapula. And his right hand's ring finger. The first joint remained bent unnaturally, immobile. Both were souvenirs from the Mibu-no incident. Across the river, the riverbed still empty of people. Reeds swayed in the wind. Was something there, beyond them? Or nothing? Soshin stared at that landscape for several seconds. Nothing abnormal. Soshin began running again. At double the pace of the outbound journey, he headed straight for home. --- He arrived at his apartment building, "Green Heights Seta-oka," at six fifteen. A twenty-eight-year-old three-story apartment complex. Twelve minutes on foot from Seta-oka Station. Open sightlines around the building, multiple escape routes secured. Second floor, corner unit. These were all the conditions Soshin had specified. He climbed the stairs to shower after his run. At that moment— A mailbox entered the edge of his vision. Normally, mail did not arrive at this hour. Deliveries were the same. Soshin stopped. The next instant, a small alarm sounded in the back of his mind. Alert level rose. He descended the stairs and checked the mailbox. A single white envelope lay inside. It appeared to be nothing more than an ordinary envelope. Yet Soshin observed it without touching. No sender listed. The postmark was unclear. Nothing printed on the front. Blank. Soshin retrieved a toothpick and carefully lifted the envelope. From its weight, he deduced the contents were either several sheets of paper or perhaps blank pages. He returned to his room and opened the envelope. Indeed, blank paper. Nothing written. Soshin held the envelope up to the light. No watermark. No special printing. Only white paper. But in the next instant, Soshin's expression stiffened for just a moment. The fold—the angle and position of the tri-fold matched exactly with the unofficial communication protocol once used by the Fourth Action Squad. A cryptographic communication method where specific angles and fold positions conveyed meaning. Only unit members knew this fold. Each person was instructed in subtly different techniques by their instructor—an extremely personal method. To outsiders, this would appear nothing more than an incomprehensible folding habit. The blank paper was a cipher meaning: "Contact preparation complete. Awaiting response." Soshin walked around the entire room. Windows, door, ventilation shaft. All locked. No signs of intrusion. Then when had this been deposited? Last night? Deep night? Or days ago? His running pattern was identical every day. Knowing this weakness, depositing it between five and six-thirty in the morning would be simple. Soshin moved to discard the envelope and paper. But his hand stopped. He descended beneath the bed and removed a section of floorboard. A hidden safe appeared. He unlocked it. Inside lay forged IDs, five hundred thousand yen in cash, and a disposable mobile phone. He placed the blank envelope inside. Soshin sat on the bed, holding the envelope, and became still. The Mibu-no incident. Seven years ago. An old communications relay station in the mountains of western Kanagawa Prefecture. What happened there. There was no need to remember. Only his own misjudgment was certain. As a result, multiple people's lives had been twisted. Who had been twisted. What had been twisted. He did not recall the specifics. By not doing so, Soshin lived. But now, this blank envelope was forcing that lid open. He looked out the window. The curtain of the house across the way trembled slightly. Was someone watching? Or was it his imagination? Soshin stood and began analyzing the situation quietly, calmly. --- Eight in the morning. He showered and changed into a suit. A white, unmarked dress shirt. Gray slacks. Black leather shoes. The watch remained. This appearance suited Soshin. Unremarkable, forgettable, appearing as an ordinary person one might see anywhere. His face reflected in the mirror remained expressionless as always. Eyes of grayish tone reflected no emotion. The envelope matter was set aside for now. Today he would report to Vectra Corporation as usual. This was Soshin's judgment. Showing abnormality meant someone would detect that abnormality. To blend into ordinary society, one had to be thoroughly normal. He wedged a single hair in the gap of the apartment door. If it had moved upon his return, it would be evidence of intrusion. Descending the apartment stairs, Soshin made his decision. The past was not finished. And now, it was beginning again. --- JR Nishi-Tama Line's Seta-oka Station experienced its heaviest congestion between seven fifty and eight twenty in the morning. Commuter rush. Soshin always avoided this time, boarding the eight-thirty train instead. The rear of the car, near the door. The exit remained in his field of vision, allowing constant monitoring of surroundings. The salaryman standing beside him, the student across from him—they were merely background to Soshin. He transferred to the Chuo Line at Shinjuku, exiting at Akasaka. Akasaka TSK Building. Twelve stories above ground, fifteen years old. Building security operated twenty-four hours, but passing through the security gate, he entered the Vectra Corporation floor on the ninth level. IC card authentication and biometric authentication. Soshin cleared these without question every day. Rather, the existence of this authentication reassured him. Ninth floor. Approximately thirty employees were already at work. Desks lined the open space in the center of the floor, with six private booths along the walls. Soshin's seat was at the window's edge. A position overlooking the entrance. He had chosen this place himself. He powered on his computer. Checked email. No urgent matters. An ordinary Monday. Yet Soshin's vigilance did not ease. The white envelope. Its fold. Its meaning. And now— An internal line rang. A name appeared on the screen. Makino. His supervisor. Soshin picked up the receiver. "Good morning." "Aizaka, come here now." Brief, emotionless voice. Makino always spoke this way. Soshin stood and headed toward Makino's private office at the rear of the ninth floor. --- Makino's office was a narrow room adjacent to a windowless conference room. Mid-forties. Short hair. Black-framed glasses. Expressionless. If Soshin was Soshin, then Makino similarly was a person in whom expression did not exist. Documents were arranged neatly on the desk. Files were color-coded, pens were placed upright, nothing unnecessary remained. Makino began immediately upon Soshin's entry. "A warehouse district in Motomachi, Yokohama. Physical security evaluation for a certain company. There are suspicious movements. Identify the intrusion route and submit a vulnerability report within three days." Soshin nodded silently. Yet something caught in the back of his mind. Vectra Corporation conducted security assessments for corporate clients. Normally, such projects required one week for preliminary investigation, three days for on-site assessment, and five days for report creation—thirteen days total. Completing an intrusion route identification and vulnerability report in three days was nearly physically impossible. This meant the client had requested the shortened timeline knowingly, implying some urgent circumstance. And Makino had not revealed the client company's name. This was a pattern that had not occurred before. "Understood," Soshin said. Yet beneath that tone lay questions. Makino would have sensed them. But he said nothing. Immediately after leaving the office— A man passed him in the hallway. Early forties. Navy suit. An unfamiliar face. Yet that man's eyes caught Soshin for an instant. It was a gaze of "confirmation." Eyes that knew Soshin. Or eyes that knew what Soshin was. The man entered Makino's office without pause. Soshin did not stop walking, returning to his seat. But his mind was organizing the situation. Who was that man? Not a Vectra Corporation employee. He wore no visitor's badge. Meaning, a person Makino had allowed through specially. And he had "confirmed" Soshin. The white envelope. This morning's deposit. Fourth Action Squad protocol. Today's unnatural assignment. The three-day deadline. The client left unnamed. And the mysterious man. Points were becoming a line. Soshin returned to his seat and faced his computer. On the surface, he worked through tasks indifferently, but his thoughts were elsewhere. This was something deliberately set in motion. And Soshin was beginning to be drawn slowly into that vortex.