In an underground laboratory base, chaos erupted without warning.
A deafening explosion tore through the structure, the shockwave blasting steel walls apart as a violent gust of wind surged through the corridors like a raging storm.
The air itself seemed to roar as debris scattered everywhere—glass shattering, metal bending, alarms screaming across the facility.
Villains inside the base panicked.
"W-What was that—!?"
"Someone's here—!!"
Their voices were cut short as the overwhelming force sent them crashing into walls and floors, their bodies going limp as unconsciousness claimed them one after another.
Through the settling dust, a towering figure stepped forward.
"I Am Here!"
All Might entered the destroyed corridor, his presence alone overwhelming, his muscular form casting a long shadow through the broken lab.
Beside him walked his trusted sidekick, Sir Nighteye, calm and composed despite the destruction around them.
Sir Nighteye's eyes glowed a faint purple, his quirk activated as he stared into the unseen threads of the future.
"This way."
Their footsteps echoed through the ruined hallways as they moved deeper into the base.
The things around them told a story of cruelty—broken chambers, discarded equipment, faint stains that spoke of experiments long since conducted.
All Might's jaw tightened.
What kind of place is this…?
They soon reached a reinforced door, half-destroyed from the explosion. With a simple push, it gave way.
The moment they stepped inside, both of them stopped.
At the center of the room stood a massive glass chamber, surrounded by complex medical equipment, wires, and monitors still flickering with unstable readings.
Inside the chamber was A child.
A small boy, no older than eight, floated unconscious within a translucent liquid, his white hair drifting gently, his fragile body covered in faint marks and scars from countless procedures.
All Might's fist clenched tightly, his entire body trembling—not from fear, but from anger.
"They experimented… on a child?"
Beside him, Sir Nighteye's glowing eyes slowly dimmed, returning to their usual yellow.
"It is All For One we are talking about," he said calmly, "He is the most evil existence in the world, after all."
He walked toward a nearby computer and typed some things.
The chamber responded.
With a low hiss, the liquid inside began to drain, the level slowly lowering as the boy's body descended. Mechanical locks disengaged, and the glass chamber opened.
The boy's unconscious form tilted forward—But before he could fall, All Might stepped forward instantly, catching him in his arms with surprising gentleness.
For someone so powerful, his grip was careful.
Sir Nighteye moved to the side, gathering documents, files, and data regarding the experiments conducted on the child.
His eyes scanned everything, selecting only what mattered as distant police sirens began to echo from outside.
"They're here," he said. "Let's go. The police will handle the rest."
All Might looked down at the boy in his arms, his expression unreadable for a moment.
"Why are you so fixated on taking this boy with us?" he asked, wrapping a nearby cloth around the child to cover him. "I don't have a problem with it… I'm just asking."
Sir Nighteye didn't stop what he was doing. He copied the data into a small pendrive, then proceeded to erase every trace of it from the system.
"I saw some things in the future," he said gravely. "And I wanted to get him out of All For One's hands as soon as possible."
The final files were deleted.
Without another word, the two of them left the room, exiting the collapsing base just as police forces began swarming the area—apprehending the remaining villains and securing the facility.
An hour later.
They stood inside U.A. High School—specifically, within the medical room of Recovery Girl.
The unconscious boy lay on a bed, bandaged and still.
Recovery Girl moved around him carefully, running detailed examinations, she checked his vitals and the extent of his injuries.
Standing nearby were Principal Nezu, Gran Torino, Sir Nighteye, and All Might.
Principal Nezu held the pendrive, reviewing the information stored within it through his laptop. His expression, though calm, was serious.
"You made the right decision prioritizing this boy over directly pursuing All For One," he said, glancing at Sir Nighteye.
Gran Torino frowned, crossing his arms. "Just what is going on here?" he demanded. "Can someone explain?"
Nezu nodded slightly.
"The boy…" he began, "is, biologically, All For One's son."
Silence.
Everyone—except Sir Nighteye—stared in shock.
All Might's eyes widened while Gran Torino's expression hardened.
Nezu continued, as if discussing something purely logical.
"This pendrive contains extensive data on All For One's quirk," he said. "While it allows the user to take and use others' quirks, it is not without its limitations."
He paused briefly, letting the weight of his words settle.
"Firstly, quirks carry fragments of a person's consciousness—one might even call it a soul. These remnants can clash within All For One's internal quirk space, where the stolen abilities are stored."
The room remained silent, every word sinking in.
"Secondly," Nezu continued, "as quirks evolve with each generation, All For One's original body—being from an earlier era—struggles to properly handle modern, more complex quirks."
Gran Torino's eyes narrowed. "…So?"
Nezu's gaze shifted toward the unconscious boy.
"So… he sought to create a new body." The implication of his words hit immediately.
"To transfer his consciousness into it," Nezu said calmly. "And, in the process, create a perfected version of his quirk—one capable of handling the evolution of quirks without limitation."
All Might's fists tightened, his knuckles turning white.
Nezu nodded toward the boy. "He used his own DNA… and created this child."
"His name is Akira Tenma."
The room fell into a heavy silence. Gran Torino exhaled sharply, shaking his head.
"That man knows no bounds for immorality," he muttered. "Creating a son… just to steal his body…"
Nezu continued, his tone unchanged.
"Akira possesses All For One's quirk," he said. "And based on these documents… it has likely been modified."
Another silence followed. Then Gran Torino spoke again.
"So what do we do with him?"
Recovery Girl straightened slightly, glancing at the group.
"The boy's condition is stable now," she said. "I've treated the damage from the surgeries performed on him. He'll recover… physically, at least."
All Might stepped forward slightly, looking at the boy.
"…Why not guide him to become a hero?"
The room turned toward him.
Nezu and Recovery Girl remained neutral. But Sir Nighteye and Gran Torino stared at him in disbelief.
"Are you nuts!?" Gran Torino snapped. "How will he be a hero!?"
But All Might didn't back down.
"This child has done nothing wrong," he said firmly. "He did not choose how he was born. He did not choose what was done to him."
His gaze hardened. "And having All For One… does not mean he will become a villain."
"Quirks don't make someone a hero or a villain," All Might continued. "It's how they choose to use them."
Sir Nighteye adjusted his glasses slightly. "…That is not a bad idea," he admitted. "There are many quirks used by villains that could benefit society—if used correctly."
Gran Torino rubbed his temples, clearly frustrated.
"We can argue about this later," he muttered. "Right now, we've got a bigger problem." His eyes hardened.
"All For One."
All Might clenched his fist, determination burning in his eyes.
"I'm ready."
Sir Nighteye's expression turned serious. "From the future I've seen… All For One is hiding near Shibuya."
A brief silence enveloped the room.
"Then that's where we'll go," All Might said immediately.
He turned toward Nezu and Recovery Girl.
"I request that you look after the boy… until All For One is dealt with."
Nezu gave a small nod. "Leave it to me."
Recovery Girl sighed lightly. "He won't be waking up anytime soon anyway," she said. "You can go."
All Might nodded. Without another word, he, Gran Torino, and Sir Nighteye turned and walked out of the infirmary.
As the door opened, All Might paused for just a fraction of a second as he glanced back at Akira, before he walked out.