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!

Psychos intends to fuse with Orochi, the Monster King, which would give them immense power against Tornado. Superalloy confronts Garo and experiences fear of his opponent's strength... Meanwhile, Saitama gets caught up in a cave-in in the Monster Association's underground labyrinth!