Izuku Midoriya: Origin

A flashback opens on a younger Izuku Midoriya stepping between a bullied child and Katsuki Bakugo, who dismisses "Deku" as a Quirkless nobody playing hero. Years later, at fourteen, Izuku watches pros fight an enormous villain. The narration explains where all of it began: a luminescent baby born in Qing Qing City, China, followed by the same phenomenon worldwide until superpowers, called Quirks, became the majority condition and heroism became a profession.

At the scene, Backdraft holds the public back while Kamui Woods lists the giant's crimes and binds him with Lacquered Chain Prison, only for Mt. Lady to barge in, finish the villain with Canyon Cannon, and announce her debut to a wall of cameras. Izuku scribbles notes on Gigantification, and a passerby wishes him luck on becoming a hero.

At Aldera Junior High the teacher hands out career forms assuming the whole class wants the hero course. Katsuki refuses to be lumped in and declares he will pass All Might at the top. When the teacher mentions that Izuku is also aiming for U.A., the room laughs. Katsuki aims an explosion his way and tells him studying will not get a Quirkless kid anywhere near his level; Izuku answers that he is not competing, only chasing a dream he has held since childhood, and that he cannot know unless he tries. Afterward Katsuki blows up his notebook and throws it out the window, telling him to give up and dive off the roof.

Retrieving it, Izuku remembers the video of All Might's debut rescue of over a hundred people, the doctor pointing at his pinky toe, two joints there and therefore no Quirk, and his mother crying and apologizing rather than answering whether he could still be a hero. Walking home, he is seized by a slime villain loose in the city. All Might arrives, wipes it out with Texas Smash, and Izuku faints. He wakes to find his idol over him, asks for an autograph, and discovers it is already in his notebook. As All Might leaves with the villain in custody, Izuku grabs his leg and goes airborne. Told to let go, he points out that he would die, so All Might hunts for a landing spot while blood runs from his mouth. On a rooftop, Izuku asks the question: could someone without a Quirk still be a hero?

Quirks are introduced as a worldwide phenomenon traced back to the luminescent baby of Qing Qing City. Kamui Woods and Mt. Lady take down the Giant Villain at the station, with Mt. Lady debuting on the spot. Katsuki destroys Izuku's hero notebook. The Sludge Villain attacks Izuku, and All Might defeats him with Texas Smash. All Might begins coughing blood, and the episode closes on Izuku's question about Quirkless heroism.

The episode adapts the first thirty pages of Chapter 1, airing in Japan on 3 April 2016 and in the United States on 5 May 2018, with THE DAY as the opening and HEROES as the ending.

It reorders and expands a fair amount. Katsuki's assault begins before the flash forward in print, while the anime cuts away and returns to the aftermath. The luminescent baby is held by a doctor on the page and lies in a crib on screen, and silhouettes of famous American and Japanese superheroes vanish, most likely over copyright. The station fight is stretched considerably: Slugger and Airjet lose their early appearances and debut later, Death Arms gains a scene catching a broken power pole plus his "Punching Hero" epithet, Backdraft gains a water fence and a rescue specialist label, and Kamui Woods enters as Izuku pushes through the crowd rather than mid-fight.

All Might approaches the crowd coughing blood in the manga and exits a convenience store without coughing in the anime. Fewer students remain in the classroom during the bullying, Inko hugs Izuku directly instead of around a chair, and the Sludge Villain attacks inside the tunnel rather than at its exit. His possessed form is drawn much larger on screen, a choice later walked back toward manga proportions in Season 7.