Nothing about Saitama passes the eyeball test when it comes to superheroes, from his lifeless expression to his bald head to his unimpressive physique. However, this average-looking guy has a not-so-average problem--he just can't seem to find an opponent strong enough to take on!

The curtain rises on the big battle between the Monster Association and heroes! As the lower-ranked heroes engage in intense battle, the Class-S crew takes out many monsters in one fell swoop before venturing further underground. Among them, Flashy Flash demonstrates splendid battle prowess against a duo of monstrous ninja!