The world inside the human body pulsed with energy — a boundless, living city powered by every heartbeat. Crimson rivers coursed through branching tunnels, and you were among the countless citizens drifting with purpose through them — a red blood cell, newly born from the bone marrow and eager for your first mission.
You were born in the Bone Marrow District, deep within the spongy heart of the bones. Around you, thousands of other young recruits stood waiting for their first deployment. You adjusted the crimson jacket of your new uniform, the symbol of the Erythrocyte Corps glinting proudly on your chest.
You are Red Blood Cell 0113, one of the newest couriers in the circulatory system. Your purpose is simple, but vital: to carry oxygen from the lungs to every corner of the body, and bring back carbon dioxide to exhale. A senior red blood cell beside you chuckled. “First run?”
You nodded. “Yes, sir. I’m ready!”
“Good. Follow the flow, and don’t fight the current. You’ll get the rhythm soon enough.”
“Erythrocyte Corps, prepare for deployment!”
The Artery Highway stretched endlessly ahead, glowing with warmth and motion. The heartbeat’s steady rhythm guided your path — each thump propelling you forward through the vast tunnels. Platelets zipped by, white blood cells patrolled the walls, and other erythrocytes glided alongside you, their movements smooth and practiced. The body was alive with purpose, each cell fulfilling its role.
You approached the Lung Sector, where enormous alveolar domes loomed like clouds. Oxygen shimmered in the air, swirling around you in bright, silver-blue waves. As you passed through, your hemoglobin tanks filled, your crimson hue deepening as oxygen bound to the iron within you.
It was beautiful — a silent, sacred exchange. You were ready to carry life itself.
But then, everything changed.
The current stuttered. The air around you thickened. A shrill alarm reverberated through the bloodstream. The calm pulse of the heart quickened into panic.
“ALERT! Pathogenic breach detected in the Lung Sector!”
The plasma churned as the oxygen mist darkened. Shapes flickered in the haze — sharp, foreign, and fast. One emerged ahead of you: a dark, spherical figure covered in jagged spikes. It twisted unnaturally, gliding with a speed that defied the current. The surrounding cells recoiled in fear as the creature latched onto the alveolar wall, injecting its genetic material inside. The once-glowing cell dimmed, shuddering violently.
You froze, realization dawning. It was an Influenza A virus — a master of infection, swift and ruthless.
More appeared, multiplying, spreading through the lung tissue like wildfire. The plasma became a storm of chemical distress signals. You tried to stay clear, but the current pulled you closer to the chaos. The virus turned, its spikes gleaming as it closed in.
And then — a flash.
The air exploded with kinetic energy as a shadow cut through the plasma. A figure descended between you and the virus — tall, armored, and radiating authority. The emblem on his chestplate read O469. His presence alone commanded silence.
“Pathogen detected,” he said, voice like steel.
The Influenza virus hissed and lunged, but O469 was already moving. With one smooth motion, he drew his weapon — not metal, but pure enzymatic energy shaped like a massive blade. His arm split into glowing pseudopodia that lashed outward, coiling around the virus and pulling it into a radiant sphere.
“Engulfed,” he muttered.
The phagosome sealed shut, glowing brightly. Within seconds, lysosomal enzymes flooded in, dissolving the virus molecule by molecule. The sphere flickered — then went dark.
Silence returned.
O469 exhaled, resting his enormous weapon on his shoulder. “Another one down,” he said, a smirk tugging at his lips. His armor gleamed under the plasma’s light, his every movement deliberate and proud.
A neutrophil passing by muttered, “Here we go again…”
O469 shot him a glare. “Jealousy doesn’t suit you, Neutrophil O302.”
Turning back to you, he softened slightly. “You okay, rookie?”