The episode opens on a busy street at night. A young man and woman are walking when they spot an older woman with white, tangled hair sitting on a piece of cardboard, drinking straight from a bottle. Strange, spiked growths cover her left arm. When the young woman tries to ask if she’s okay, the older woman hurls the bottle at her and screams for them to leave.
They run off, and the woman stays behind, clutching her stomach. She’s pregnant—with twins. One is growing abnormally large, draining her life and leaving the other frail and underdeveloped.
Later, her body is found by a river in the pouring rain. The twins are born anyway. The larger one starts gnawing on their mother’s body, even eating the spiked growths, while holding the hand of his tiny, barely-breathing brother. As the storm worsens, the river floods and sweeps them both away.
The birth of Meta abilities
Not long after the twins are born, word spreads about a strange case in China — a glowing baby. The story goes viral, and soon more reports start showing up around the world. People born with mysterious powers. Some even awakening them at puberty. They call these powers “Meta Abilities.” At first, scientists think it’s a disease, or maybe a mutation that split humanity into something new. But that theory only makes things worse. The world falls into chaos as people with and without powers start fighting to decide who really counts as human.
In the middle of all this is the older twin. He’s born with a Meta Ability too — one that lets him steal other people’s powers and even pass them on. The first one he takes comes from his own mother, when he eats the strange growths on her body. Later, people will call that ability “Spearlike Bones.”
While the world tears itself apart, the older brother does the same on his own terms. He’s selfish, cruel, and believes everything he sees belongs to him. Anyone who doesn’t give him what he wants — even attention — is an enemy. His way of dealing with them? Murder. Sometimes, he even steals their powers for himself — whether they’re mercenaries hunting powered people, or just thugs unlucky enough to cross his path.
One for all, and all for one
One day, the younger brother is caught reading a stack of books. When his older brother asks what he’s reading, the boy admits they’re comic books. Since his reading skills aren’t great yet, he sticks to the ones with pictures. He says he likes them because the art alone shows him the dreams of the people who make them. Looking at the main character of Captain Hero, he says he wants to be just like him someday.
Three years later, the younger brother, now older, is reading again when his brother interrupts him. The older brother floats down in front of the moon and says that the glowing child from China has grown up and become a major peace figure with ten million followers. As he lands, the younger brother notices he’s glowing too. The older brother mentions it’s strange and reminds him that the peace advocate was the first person recorded with a Meta Ability, though rumors say dozens in India were born with powers two weeks earlier.
The younger brother is shocked to see his brother covered in blood. The older one admits he killed the peace figure and stole his power, saying it’s odd how someone like that could bring people together. When the younger brother presses him, he points to their old Captain Hero comics and quotes, “One for all, and all for one.” He explains that while the Hero hides his identity to fight evil alone, the Demon Lord rules through fear. He compares them to that same dynamic and says he’s found his own dream — a world where everything exists for him alone.
Death of Yoichi
AFO looks down on his brother, pitying him for being born powerless and claiming that no one could ever take him seriously. He grabs his brother’s face and tells him that now his dreams have come true, he’s going to remake the one where his brother keeps defying him. Ignoring Yoichi’s desperate protests, All For One forces a Meta Ability into him—something his weak body can supposedly handle. As Yoichi screams in pain, All For One gives him a name for the first time: Yoichi—because his brother was the first thing ever given to him.
Later, Yoichi is discovered by resistance members Kudo and Bruce. The group tries to escape through the sewers as All For One chases after them. Calmly, he calls out to his brother, demanding to know why he’s running away when he’s “property” that All For One “graciously” granted power to. But as Kudo and Yoichi keep fleeing, All For One’s patience wears thin. His voice shifts from calm to furious—he’s done being ignored, enraged that Yoichi dares to live free from his control.
All For One effortlessly waves his hand and rips Yoichi’s body apart. Kudo gets splattered with blood as Bruce grabs him and the soldiers retreat. The only thing left of Yoichi is his hand, which falls into the wastewater below. Kudo, shaken, looks back at All For One and notices how lifeless his eyes are—like there’s nothing human left in him.
One For All passes for the first time
Back at his tower, All For One studies his brother’s severed hand and realizes something’s off. The power he forced into Yoichi has vanished. He once believed Yoichi didn’t have a Meta Ability at all—maybe one he’d already taken without knowing—but now he discovers that Yoichi’s ability was there the whole time, just too weak to detect. Digging deeper, All For One figures out that Yoichi’s ability activated before he died, absorbing the power implanted in him. That means Yoichi’s will didn’t die with him—it moved on.
Meanwhile, Kudo and Bruce start to piece it together. After their last fight, Kudo tells Bruce his body’s been feeling strange, so Bruce runs some tests. The results show Kudo now holds two Meta Abilities—his own and Yoichi’s. Realizing what that means, Kudo looks at his hand and understands that Yoichi’s will is still alive inside him.
All For One continues to grow in power and influence as he kills anyone that has his brothers Quirk. Unfortunately, for him One For All would eventually become too powerful for him to steal. When he encountered All Might the Quirk was strong enough for All Might to defeat him, however, AFO survived with the help of Kyudai Garaki.
Dynamight ends AFO’s reign
In the present, AFO is enraged by the fact that Dynamight resembles Kudo so much. However, time running out, pressuring him to end the fight. He decides to combine every Quirk he has leaving just enough for his plan. He uses a massive amount of energy to propel his now massive form at Dynamight. Despite a plea from All Might to dodge, Dynamight uses delayed Explosive sweat he coated in regular sweat. All For One momentum halts and he crashes to the ground.
Dynamight then uses his Howitzer Impact: Cluster, overwhelming the villain. He reduces All For One to an infant, while the villain tries to attack in a last ditch effort, he fails to harm Dynamight. He begins to regress back to a fetus, than a zygote, and finally nothing. Dynamight collapses to the ground, victorious.
