Season 1
Episode: 1x01 | Airdate: Oct 6, 2015
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. Though he's now so strong he can defeat any opponent with a single punch, lately he feels as if, in exchange for overwhelming power, he's lost something even more important.
Episode: 1x02 | Airdate: Oct 13, 2015
A monster is moving toward City Z, one that has been created by the mysterious organization known as The House of Evolution. Genos, a young cyborg, attempts to stop it, but gets in over his head before Saitama happens along.
Episode: 1x03 | Airdate: Oct 20, 2015
Saitama and Genos track down an evil scientist who wants to know the secret to Saitama's power.
Episode: 1x04 | Airdate: Oct 27, 2015
A group of battlesuit-clad terrorists called "The Paradisers" appears in City F, led by an enormous man known as Hammerhead. Calling for the redistribution of wealth, the group targets the fat-cat Zeniru, who in turn dispatches his bodyguard to defeat them. Unfortunately, Saitama is on the same errand.
Episode: 1x05 | Airdate: Nov 3, 2015
Saitama and Genos find out about the hero registration and both take the tests to certify. Genos gets "S(Special)" and Saitama gets a "C" grade. Meanwhile, Genos became the disciple of Saitama and learned about the power of saitama's punch on a training session.
Episode: 1x06 | Airdate: Nov 10, 2015
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, Saitama heads out on patrol, yet can't find any criminals or monsters to stop.
Episode: 1x07 | Airdate: Nov 17, 2015
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.
Episode: 1x08 | Airdate: Nov 24, 2015
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.
Episode: 1x09 | Airdate: Dec 1, 2015
The Deep Sea King has defeated every hero who opposed him with ease. Genos is preparing to attack while Licenseless-Rider and Saitama rush to the evacuation shelter, where the battle continues.
Episode: 1x10 | Airdate: Dec 8, 2015
Saitama tags along to an emergency meeting of Class S heroes and discovers that a seer has foretold a serious danger threatening the Earth. Though the crisis could occur anytime in the next six months, the heroes are surprised to hear the roar of explosions that very hour!
Episode: 1x11 | Airdate: Dec 15, 2015
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 on his own.
Episode: 1x12 | Airdate: Dec 22, 2015
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 the worthy opponent they've been searching for?
Season 2
Episode: 2x01 | Airdate: Apr 9, 2019
Saitama and Genos are out shopping when they come across G4, a demonic robot on a mission to eliminate King. Meanwhile, Sitch attempts to recruit various assassins and villains.
Episode: 2x02 | Airdate: Apr 16, 2019
Garou issues a declaration of war on the Hero Association through terrifying means, Hellish Blizzard gives Saitama an ultimatum, and Genos decides to eliminate his master's stalker, Speed-o'.
Episode: 2x03 | Airdate: Apr 23, 2019
Garou, out hunting heroes, can barely contain his excitement when he gets the chance to battle the S Class hero Tank-top Master. Meanwhile, Silverfang shutters his dojo to begin his own hunt of his former disciple.
Episode: 2x04 | Airdate: Apr 30, 2019
Assigned to guard a VIP and his son, Metal Bat couldn't be less thrilled. But when the group is suddenly attacked all hell breaks loose. Meanwhile, Saitama has disguised himself as Charanko in order to enter the "Super Fight" martial arts tournament.
Episode: 2x05 | Airdate: May 7, 2019
Monsters from the Monster Association launch simultaneous attacks on all the human cities, attempting to overwhelm the forces of the Hero Association. Meanwhile, the "Super Fight" martial arts tournament kicks off.
Episode: 2x06 | Airdate: May 14, 2019
The Super Fight tournament kicks off while Genos takes on multiple monsters who have appeared in City C. Elsewhere, countless monsters are wreaking havoc in multiple areas, but the Hero Association is being overwhelmed by the sheer number of threats.
Episode: 2x07 | Airdate: May 21, 2019
As the Super Fight tournament heads for its grand finale, the Class S heroes battle to hold back the tide of monster incursions. Meanwhile, Atomic Samurai is setting in motion a plan of his own.
Episode: 2x08 | Airdate: May 28, 2019
Goketsu, the first Super Fight Tournament champion, arrives in the stadium. Having now become a monster, he's aiming to force the Super Fight competitors to turn into monsters themselves. When several do, it's up to Suiryu to take them on alone.
Episode: 2x09 | Airdate: Jun 11, 2019
Saitama returns to the battle, but is starting to get through a gloomy state because of an obvious reason.
Episode: 2x10 | Airdate: Jun 18, 2019
The Monster Association invited all of the S-Class heroes to their hideout in City Z. Meanwhile, Garo encounters a serious threat.
Episode: 2x11 | Airdate: Jun 25, 2019
Garou is at last surrounded by multiple heroes and forced to fight, even though he's covered in wounds and nearly at his limit. The hero hunter still has his incredible ability to read opponents' fighting styles, but there are surprises in store for all.
Episode: 2x12 | Airdate: Jul 2, 2019
As the fight continues between Garou and his former master, Bang, a prominent threat from the Monster Association reappears.
Specials
Episode: S01 Special | Airdate: Dec 4, 2015
Episode: S01 Special | Airdate: Dec 24, 2015
Episode: S01 Special | Airdate: Jan 29, 2016
Episode: S01 Special | Airdate: Feb 24, 2016 (11 min)
Sonic trains in the woods, trying to deal with his defeat. Whilst trying to become stronger he makes unexpected friend.
Episode: S01 Special | Airdate: Mar 25, 2016 (11 min)
Episode: S01 Special | Airdate: Apr 22, 2016 (11 min)
Episode: S01 Special | Airdate: May 27, 2016 (11 min)
Episode: S02 Special | Airdate: Apr 2, 2019 (24 min)
The anime's website describes the April 2 airing in Japan as the "broadcast premiere commemorative special."
Episode: S02 Special | Airdate: Oct 25, 2019 (15 min)
Included in the first BD/DVD volume.
Episode: S02 Special | Airdate: Nov 25, 2019 (10 min)
Included in the second BD/DVD volume.
Episode: S02 Special | Airdate: Dec 25, 2019 (12 min)
Episode: S02 Special | Airdate: Jan 28, 2020 (12 min)
Episode: S02 Special | Airdate: Feb 27, 2020
Episode: S02 Special | Airdate: Mar 27, 2020