Written by Tomohiro Suzuki. Originally a manga created as a webcomic in 2009 by the artist ONE, Who is still releasing it to this day. The anime currently has 2 seasons with a total of 24 episodes, it’s safe to say that if we do get the 3rd season in the coming years, That it will probably have 12 episodes as well.
The plot revolves around Saitama an unemployed 25-year-old hero and his student Genos a 19-year-old cyborg.
One punch man orgin: how Saitama and genos got where they are
After Saitama saved a young boy from a giant crab monster he began training for three years to become the hero he dreamed of as a child. 1 year before Saitama saved that boy a cyborg had destroyed a city nearly killing 15-year-old Genos, Who would have died if not for Dr. Kuseno who saved his life by making him the cyborg he is today. After Genos saw how strong Saitama was, he forced him to take him as his student, in hopes of learning how to get that strong.
The hero association
Time went on before Saitama realized no one knew who he was despite the countless amount of monsters that he killed. Through Genos he learned about the hero association. The hero association is an organization founded by multi-millionaire Agoni after his grandson was nearly killed by a mysterious crab-like monster.
There are four ranks in the association ( C, B, A, and S) Genos had been put with the S rank heroes. The highest rank of heroes, meanwhile Saitama had been put with the C rank heroes the lowest rank of heroes. Despite his enormous strength. Even though he had defeated a multitude of monsters, that even KING the highest-ranking S rank hero couldn’t takedown. Still, most of the heroes would say that he was cheating or that another hero had already weakened them. despite that, he battled monsters till the day a universal group of thieves known as “Dark Matter” came to earth.
lord boros and dark matter
Boros the leader of Dark Matter sent a multitude of alien warriors to fight the hero association. Meanwhile, Saitama snuck aboard the Dark Matter’s ship and killed any aliens who got in his way. Until he found their leader, Lord Boros. Soon a fight broke out. And in my opinion, this is by far the best fight in all of the One punch man TV show. just because Lord Boros is the first person EVER! in the OPM universe to survive one of Saitama’s punches in fact he survived a multitude of punches before the fight ended. Though none of the heroes even knew that Boros existed. Nor that Saitama had defeated. Meaning Saitama got no credit for saving everyone and everything on earth.