Dark Hero Arc

Nineteenth in the run of My Hero Academia story arcs, and the first belonging to the Final Act Saga. It covers chapters 307 through 328, adapted across Episodes 132 to 138 plus the four Memories installments numbered 138.1 to 138.4. It follows the Paranormal Liberation War arc and leads into the Star and Stripe arc.

Hero society has been sliding since the war ended. Tomura Shigaraki emptied the prisons, so most of Japan's worst, All For One among them, are loose. Holding the country's fate, Deku leaves U.A. High School to hunt the League's remnants alongside All Might, Endeavor, Hawks and Best Jeanist, while forcing One For All toward its full power before the last fight arrives.

In the vestige realm, Yoichi Shigaraki talks the second and third users into backing Izuku's plan to save Tomura, reminding the second that he himself was spared once by men who had come to kill him. Awake at Central Hospital, Izuku learns his body now handles forty-five percent rather than five, which is why the damage stayed near the surface. He and All Might tell Inko Midoriya the truth about One For All, and then he tells her he is not going back to school. Tomura can find him, and he will not have anyone else hurt. All Might refuses to let him go alone. Best Jeanist agrees to the shape of it: Izuku as bait, the top three trailing at a distance to keep the arrangement quiet. Gran Torino hands over his cape on the way out.

Muscular, calling himself Jailbreaker, is tearing through an abandoned city when a hooded Deku drops on him and ends the rematch in one blow, using Smokescreen, Float, Danger Sense and Blackwhip as tools rather than finishers. He asks the man whether any other road was ever open to him, and gets nothing back.

All For One then sends Lady Nagant, a former Public Safety Commission marksman he freed from Tartarus, paying her in advance with the Air Walk Quirk. She brings Kai Chisaki along to identify the target. Their duel becomes an argument: she killed for years to keep a fragile illusion standing, shot the Commission president when he told her the job had no exit, and now considers even a world under All For One more honest than the one she served. Deku answers that the world is mostly grey, which is exactly why a hand has to be offered. He unlocks Fa Jin mid-fight, improvises Faux 100 Percent to outrun a bullet aimed at Kai, and breaks her rifle arm. Then he catches her, telling her the shot was never meant to land and that the hero in her is still there. Her body detonates before she can answer, a failsafe All For One installed against exactly this. She survives, names Haibori Woods and a two-month deadline, and Hawks takes her in.

The mansion is a trap and a taunt. Deku keeps working, refusing rest, shrugging off All Might until the man is left reaching after him. Rumors spread that the ragged figure with many Quirks might be a Nomu. Death Arms retires, worn down by the criticism. When Dictator turns a crowd of controlled civilians on an exhausted Deku, Class 1-A arrives.

They had cornered Endeavor through Nezu until he handed over the location. What follows is less a fight than a class refusing to be dismissed, each of them throwing his own words back at him. Ochaco Uraraka, Shoto Todoroki, Fumikage Tokoyami, Mezo Shoji and the rest wear him down until Ingenium catches his hand and will not let go, and Dynamight, who has never apologized for anything, apologizes for all of it and calls him Izuku.

Back at U.A., civilians sheltering inside protest his return, correctly naming him a target. Best Jeanist's explanation fails. Ochaco climbs the building with a microphone and argues that special powers exist but special people do not, that this boy left to spare them and came back only because his classmates dragged him, and that the people who are covered in filth should be allowed to wash it off. The crowd turns. Kota Izumi and a woman Deku once saved reach him first, and he collapses in tears.

Nezu reveals the U.A. Barrier: every section of the school drops into a mobile underground shelter running through tunnels beneath three thousand layers of Bulwark plate, designed and paid for by him against Tomura's Decay, with Shiketsu High School fortified and allied alongside.

All Might, meanwhile, meets Stain at the Kamino statue. The Hero Killer tells him his heroism was never a matter of his Quirk at all, that the embers he left behind are catching, and throws him a knife holding data stolen from Tartarus. Read against the Nomu research and the captured assassins, the recording of All For One speaking to his own vestige through Radio Waves gives a figure nobody wanted: Tomura will not be complete in two months, but in three days. All Might calls on the world, the U.N. hesitates, and America's Star and Stripe leaves for Japan on her own.