A hero becomes so strong from training that he can take out his worst foes with one punch, but strength has lost him his hair and fighting passion.
S01:E01 - The Strongest Man
Saitama is a guy who’s a hero for fun. After saving a child from certain death, he decided to become a hero and trained hard for three years.
S01:E02 - The Lone Cyborg
A monster is moving toward City Z, one that has been created by the mysterious organization known as The House of Evolution.
S01:E03 - The Obsessive Scientist
Saitama and Genos glean information about The House of Evolution and its founder Dr. Genus...
S01:E04 - The Modern Ninja
A group of battlesuit-clad terrorists called The Paradisers appears in City F.
S01:E05 - The Ultimate Master
Saitama decides to become a professional hero and takes the test with Genos.
S01:E06 - The Terrifying City
It's been five days since Saitama became a professional hero and he has yet to do anything heroic. When Genos informs him that C-class heroes who don't fight bad guys are dropped from the hero registry after a week of inaction...
S01:E07 - The Ultimate Disciple
An enormous meteor hurtles toward City Z, forcing the Hero Association to ask its S Class heroes to respond. When all their efforts prove in vain, Genos decides it's up to him to protect the home of his master and stop the meteor, no matter what the cost.
S01:E08 - The Deep Sea King
A pack of monsters calling themselves the "Clan of the Seafolk" arrive on the shores of City J intent on invading the land. When the hero sent to fight them is defeated easily by the Deep Sea King himself, Saitama and Genos head for the city to help.
S01:E09 - Unyielding Justice
As the battle with the Deep Sea King reaches its climax, more heroes fall to the aquatic despot's brutal attacks. Which of them has what it takes to be a true hero?
S01:E10 - Unparalleled Peril
Saitama attends an emergency meeting of Class S heroes; a seer foretells a serious danger.
S01:E11 - The Dominator of the Universe
As a colossal spaceship floats in the skies above City A, a member of its monstrous crew battles on the ground against a group of S Class heroes. Despite their powers, they can't seem to finish it off. Meanwhile, Saitama has boarded the enemy ship …
S01:E12 - The Strongest Hero
The inconceivably powerful Lord Boros has traveled untold distances in search of someone who can cure his boredom: Saitama! With the fate of humanity in the balance, will the two champions at last find in each other…