The next episode of "My Hero Academia" will revolve around the secrets of the All For One quirk. Just as episode 19 hinted, Midoriya will end up going to All Might's office wherein the latter's past will be revealed, including how he was able to attain the One For All.

In the aftermath of episode 18, the Hero Killer Stain found himself in prison. However, the League of Villains was revealed to have mobilized against the heroes and it will be only a matter of time before they make their move.

Audiences were given a quick breather to the previously intense arc of "My Hero Academia" via episode 19 since it was about the internship of the students. The episode gave the different characters some screen time, and audiences of the anime got to know them much better.

In episode 20, All Might will clarify that quirks are non-transferrable, which means that even if the Hero Killer Stain appears to have these abilities after tasting the blood of his enemies, they do not entirely become his quirks.

Following the clarification by All Might, he will finally reveal the genesis of his One For All by providing an elaborate flashback of what life used to be during his younger days. He will go on to say how there was a division between those with and without quirks due to the abuse of power that was happening among quirk users.

He will then reveal that the All For One had the ability to take any quirk users' powers, and has the special ability to give these quirks to whomever he pleases. All For One will be revealed to have a brother, who once upon a time did not have powers to speak of, except that he possessed the One For All which could transfer quirks to others.

This quirk has been able to steadily gain power as time went on, and was eventually seized by All Might, which allowed him to defeat All For One later on in his life. After this explanation, Midoriya will finally realize that the One For All power currently resides in him.

"My Hero Academia" airs every Saturday at 5:30 p.m. JST on MBS.