Saitama before the suit was just another guy chasing the hero dream, broke and delusional. This OVA watches him become a parody of himself through the stupidest possible accident, which is exactly what One Punch Man is actually about. It's five minutes that explain nothing and everything at once, which makes it the most honest origin story in anime.

Back when Saitama was still a weak, cash-strapped hero in training, his constant fights kept shredding his tracksuit, and a nearby tailor patched it up for him at no charge. Then the tailor reveals he has to shut his shop because a yakuza gang is squeezing him. Saitama resolves to help, and the episode reveals the hidden origin of his hero suit. This single-episode action comedy OVA came packaged with the tenth manga volume and tells an original story by the series creator, ONE.