Saitama and Genos are returning from the grocery store when they spot King, S Class Hero Rank 7. Tongue Stretcher terrorizes the populace but immediately surrenders when confronting King due to hearing King's Engine. A robot named G4 soon challenges King to a fight, but lets King leave with his excuse of going to the bathroom so they can fight at "full power". However, G4 will start murdering innocent civilians nearby if King doesn’t return in ten minutes. King panics because he isn't the "strongest human alive", but a normal ordinary Otaku who happened to be at the right place at the right time where monsters were destroyed and was given the credit, which he started accepting to become popular. When King sees Genos fighting G4, King runs away to his house to play his video game, Heartbeart Hottie Sisters 2. Saitama follows him and King is embarrassed to be caught playing a dating sim and switches to another game. Saitama plays video games with King, much to King's chagrin. Giant Crow attacks King's apartment, and in a state of panic King wets his pants and exposes his deception. Saitama kills the bird monster, which makes King realize it was Saitama who had saved him from the monster, Octopus Claw Man, that gave him the scar on his left eye long ago. Afterwards, Saitama plays video games with King while Genos gets upgrades from G4's equipment from Dr. Kuseno after defeating the robot. Sitch announces that he will be recruiting criminals to battle monsters due to the increased rate of monster appearances and the impending prophecy from Shibabawa. With heroes stretched thin, the Hero Association is willing to Speed-o'-Sound Sonic leaves the meeting after discovering Saitama was not present, as he only attended the meeting to fight him. In Z-City, Fubuki is discussing Saitama's unusual strength and rise in ranks with Eyelashes and Mountain Ape. They head out to look for Saitama. Saitama continues playing video games with King and is visibly annoyed at King hogging all the items to the point of accidentally destroying his controller. In the post credit scene, a man named Garou proclaims that this will be a slaughter party after reading the paper.
Saitama and Genos walking with groceries and seeing the King action figure is an anime original scene.
The civilians discussing the King Engine was moved to be during King's encounter with G4, rather than after the encounter with Tongue Stretcher.
As King flees, he notices Genos fighting G4 in the distance. In the manga he did not.
Genos' fight with G4 cuts back to King and Saitama once Genos sees the fire extinguisher.
King's inner monologue about monsters being attracted to him excludes nameless monsters, featuring only Vaccine Man and Marugori. It also shows King watching the Paradisers vandalize Zeniru's home, and Saitama defeating Vaccine Man with King nearby.
King's monologue cuts back to Genos' fight with G4 when Genos throws the fire extinguisher.
Genos' fight with G4 cuts back to King and Saitama when he captures G4 in cords.
Genos' final blow on G4 is synchronized with Saitama's punch on the Giant Crow.
Saitama keeps his collared shirt on as he speaks with King after the Giant Crow's defeat.
During their conversation, Dr. Kuseno tells Genos to contact him if he gets any clues on the mad cyborg.
A shot of Shibabawa is shown when Speed-o'-Sound Sonic reads the prophecy at the meeting.
The scene of Sonic leaving the Hero Association base is moved here.
The scene of Fubuki and the Blizzard Group entering Z-City is moved here.
The episode ends with Saitama playing video games with King.
Garou's fight in the Hero Association base is moved to the next episode, though it has a short tease after the credits.