Life gets pretty boring when you can beat the snot out of any villain with just one punch. 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! In the deadly battle with the Monster Association, the heroes are all getting seriously injured. And to make matters worse, Garo appears as a monster! However, Bang is there to face him down. Who'll have the upper hand in this master-pupil showdown?!