The seemingly unimpressive Saitama has a rather unique hobby: being a hero. In order to pursue his childhood dream, Saitama relentlessly trained for three years, losing all of his hair in the process. Now, Saitama is so powerful, he can defeat any enemy with just one punch. However, having no one capable of matching his strength has led Saitama to an unexpected problem—he is no longer able to enjoy the thrill of battling and has become quite bored. One day, Saitama catches the attention of 19-year-old cyborg Genos, who witnesses his power and wishes to become Saitama's disciple. Genos proposes that the two join the Hero Association in order to become certified heroes that will be recognized for their positive contributions to society. Saitama, who is shocked that no one knows who he is, quickly agrees. Meeting new allies and taking on new foes, Saitama embarks on a new journey as a member of the Hero Association to experience the excitement of battle he once felt.

It has been two and a half years since Naruto Uzumaki left Konohagakure, the Hidden Leaf Village, for intense training following events which fueled his desire to be stronger. Now Akatsuki, the mysterious organization of elite rogue ninja, is closing in on their grand plan which may threaten the safety of the entire shinobi world. Although Naruto is older and sinister events loom on the horizon, he has changed little in personality—still rambunctious and childish—though he is now far more confident and possesses an even greater determination to protect his friends and home. Come whatever may, Naruto will carry on with the fight for what is important to him, even at the expense of his own body, in the continuation of the saga about the boy who wishes to become Hokage.

Tucked in the mountains near the elite Kunugigaoka Middle School lies a small derelict building that houses the delinquents and dropouts of Class 3-E. Looked down upon by their peers, the students in this class appear to have little hope in advancing their academic careers. That is, until the national government tasks them with eliminating the greatest threat to their planet: their new teacher. Having already destroyed the moon, the octopus-like professor—dubbed Koro-sensei—has now threatened to destroy the Earth by March of the following year. In light of their mission, the students have found that killing him is easier said than done. Not only can Koro-sensei move at speeds of up to Mach 20, but he can also resist almost every earthly weapon. Ironically, he also proves to be one of the best teachers Class 3-E has ever had. Training the class to excel in both their studies as students and skills as assassins, Koro-sensei is confident that his students' ingenuity and indomitable will could return them to the main campus. Through trial and error, Nagisa Shiota, as well as the other students of Class 3-E, must figure out Koro-sensei's weaknesses—and fast, for the very fate of the world depends upon it.

All of a sudden, they arrived: parasitic aliens that descended upon Earth and quickly infiltrated humanity by burrowing into the brains of vulnerable targets. These insatiable beings acquire full control of their host and are able to morph into a variety of forms in order to feed on unsuspecting prey. Sixteen-year-old high school student Shinichi Izumi falls victim to one of these parasites, but it fails to take over his brain, ending up in his right hand instead. Unable to relocate, the parasite, now named Migi, has no choice but to rely on Shinichi in order to stay alive. Thus, the pair is forced into an uneasy coexistence and must defend themselves from hostile parasites that hope to eradicate this new threat to their species.