After seeing that Katsuki Bakugou is the one being attacked by the villain, Izuku Midoriya rushes to his aid. Remembering the notes he took by observing heroes, he then throws his bag at him and tries to grab Katsuki, but the villain's body stops him from doing so. Katsuki then yells at him, questioning why Izuku is there. Izuku says there are could be lots of reasons, but it was because Katsuki's eyes were pleading for help and he couldn't stand by and watch him die.
Stunned with Izuku's actions, All Might questions himself, saying that he's pathetic for forgetting that a pro must always put his life on the line. All Might transforms into his hero form and stops the Sludge villain from striking Midoriya. In one motion, All Might uses Detroit Smash to to blast the Sludge villain apart, and pull Bakugo from his body.
All Might sends the villain into the stratosphere just through the sheer wind pressure from his punch. Izuku is scolded by the other pro heroes for risking his life, while Katsuki is praised for fighting back against the villain and for his strong quirk.