What would happen to society if 80 percent of people developed superhuman abilities known as "Quirks"? There would be fights between heroes and villains everywhere! Learning how to wield your power is a necessary part of being a hero, but where would you go to school? Obviously the Hero Academy! But if you were one of the 20% of people who were born Quirkless, what would you do? The Hassaikai criminal organisation, headed by the teenage chief Chisaki, has been developing a scheme to spread a drug that destroys quirks. The young girl Eri, who is being held captive in Chisaki's lair, is the key to this terrible plan. The children of Class 1-A are entering the lion's den as Nighteye urges other heroes to put together a squad to undertake a rescue attempt.