Saitama Can End Any Fight in One Punch, and That’s the Joke

Saitama trained for three years and lost his hair. He gained something worse in the bargain: absolute strength, and with it absolute boredom. Every monster that threatens City Z dies in a single punch, and that is the joke, the tragedy and the whole engine of One-Punch Man.

Trailer, via vizmedia.

A Hero Who Only Became a Hero for Fun

The series opened on TV Tokyo and its affiliate network on October 5, 2015, and ran 12 episodes through December. Madhouse produced that first season. A second season from J.C.Staff followed in 2019, and a third from the same studio aired from October to December 2025. Thirty-six episodes across three seasons, with a second cours of season three set for 2027.

Makoto Furukawa voices Saitama. That performance carries the show’s central trick: a hero who sounds as flat about saving the world as he would about a grocery list.

The premise is thin on paper. On a supercontinent version of Earth, monstrous threats arrive and the Hero Association mobilizes superheroes to stop them. Saitama is unaffiliated, from City Z, and invincible. He wants an opponent who can reignite his passion for combat. He does not find one.

Genos, Mosquito Girl and the Written Exam

What saves One-Punch Man from being a one-note gag is Genos. The cybernetic warrior wants vengeance against the machine that destroyed his hometown. He nearly dies fighting Mosquito Girl. Saitama kills her without effort, and Genos becomes his devoted disciple.

Then the Hero Association’s ranking system does its work. Saitama’s poor written exam results drop him to C-Class. Genos, on the strength of his abilities, lands immediately in S-Class. It is a clean, funny piece of satire, and the show never lets it go.

The rankings matter because the show keeps testing them. Saitama stops an asteroid impact alone. He defeats the amphibious terror Deep Sea King. Public opinion then turns on the other heroes for their weakness, and Saitama draws the criticism onto himself to protect their reputations. He is not rewarded. He is not even thanked.

Boros and the Deepening Crisis

The alien warlord Boros arrives late, fulfilling the dying prophecy of the seer Shibabawa. The Association’s forces fight his army while Saitama faces the conqueror directly. The duel is one-sided. Saitama’s signature finishing move ends it.

The victory makes everything worse. The “Dominator of the Universe” could not challenge him either, and the show treats that as a genuine loss rather than a punchline.

Meanwhile Garo, the self-styled “Hero Hunter,” emerges as monster attacks escalate. Garo is a disgraced martial artist, and his arrival sets up the longer arc the later seasons carry.

Why the Boredom Works

The structure of One-Punch Man inverts the standard action series. Tension does not come from whether Saitama will win. It comes from watching everyone around him fail to understand what he is.

Here is the ranking of what the first season gets right, in order:

1. Saitama’s flat affect against escalating threats, which never stops being funny.
2. Genos as the straight man, earnest where Saitama is indifferent.
3. The Hero Association’s ranking system, a bureaucracy that mistakes paperwork for merit.
4. The asteroid and Deep Sea King arcs, where selflessness costs Saitama public standing.

The weaker material is the connective tissue between fights, where the show leans on the same joke twice.

Broadcast Dates and Where It Aired

In North America, Viz Media licensed the series. Season one aired on Adult Swim’s Toonami block from July to October 2016. Season two ran on the block from October 2019 to January 2020.

The manga behind it has its own weight. One launched the original webcomic in early 2009. Yusuke Murata’s digital remake began on Shueisha’s Tonari no Young Jump in June 2012, and as of July 2026 it stands at 37 volumes with over 38 million copies in circulation. The webcomic passed 7.9 million hits by June 2012.

None of that guarantees a good adaptation. This one earned it.

What the Punch Cannot Fix

One-Punch Man is the rare comedy that commits to its premise without wearing it out. The show understands that an invincible hero is only interesting if the world around him is not. Saitama’s problem is never the monster. It is the boredom, the ingratitude, and the paperwork.

The 2015 season holds up because it never asks you to root for the punch. It asks you to watch a man who has already won everything and has nothing left to want. That is a harder trick than it looks, and Madhouse pulls it off.

anime review · J.C.Staff · Madhouse · One-Punch Man · Saitama · TV anime