When aliens invade Earth, a group of Class-S heroes finally finds a way to fight back and go on the offensive. Inside the enemy mother ship, Saitama fights Boros. Faced with the alien’s frightful power, he decides to get serious! What is the Earth’s fate?!

Narinki’s private force is now free from Super S’s control. Bushi Drill, Okama Itachi and Iaian plot their escape, but threat level Demon monster Malong Hair appears before they can flee, and a fierce fight breaks out. Elsewhere, their master Atomic Samurai encounters a creepy opponent!

The dangerous monster that can’t be cut, Evil Mineral Water, confronts Bushi Drill, Okama Itachi, and Iaian. Meanwhile, Saitama runs into the giant demonic dog Pochi, and Terrible Tornado launches into an epic supernatural battle against Gyoro-Gyoro!

In an underground labyrinth, Puri-Puri Prisoner encounters Garo, who is now stronger than ever! Meanwhile, Saitama teams up with the hero Flash while both are lost underground. On the surface, Nyaan toys with Class-A heroes until Drive Knight appears!

Psychos and Tornado’s psychic battle rages on! With Genos’s help, Tornado succeeds in rescuing the scattered heroes from their fight against the monsters, allowing her to unleash a devastating attack that warps the city. Although the outlook appears grim, a group of S-class heroes finds the inspiration to turn the tide of battle!

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!

To stop a Demon-level crisis, Saitama and company head toward the action. However, even Class-S heroes prove to be no match for the Deep Sea King! In order to protect the good citizens, our heroes will need to summon all of their courage and confront this threat!

Despite just finishing a martial arts tournament and immediately dealing with the Monster Association invasion, Saitama still proves to be so incredibly strong that he feels empty inside. King lectures him on how to live like a hero, but it doesn’t help. Meanwhile, servants of the Monster Association close in on Speed-o’-Sound Sonic!

Surrounded by heroes, Garo finds himself in a tight spot. But despite the great numbers, he defeats the heroes one by one with his unmatched strength before Genos comes rushing in! Meanwhile, Saitama is reaching the height of irritation in his own battle…with King?!

As the fight against the Monster Association big shots heats up, Class-S heroes find themselves locked in a desperate struggle, but Tornado is closing in on Gyoro-Gyoro’s main body! Meanwhile, Blackluster confronts Garo, while Saitama wanders the labyrinth where the Monster Association is hiding out.

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!

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!