Volume 3 delves deeper into Saitama's journey as he struggles with the monotony of his overpowering abilities.
In this volume, readers can expect a blend of intense action sequences, hilarious moments, and a deeper exploration of the world of heroes and villains. Saitama's deadpan reactions and his unending search for a worthy opponent add an amusing layer to the narrative. As he continues to defeat his foes with a single punch, the story begins to introduce more complex characters, including other heroes who are both allies and rivals. Along with Genos, Saitama set out to enroll in the Hero Association Exam, to be eventually put in a rank level according to their overall assessment of their various abilities.

Saitama encounters several enemies and challenges, showcasing the variety of threats he faces in the world. One of the central antagonists of this volume is Carnage Kabuto, a powerful and savage monster with a penchant for destruction. Kabuto is a product of scientific experimentation, and his uncontrollable rage and strength make him a formidable foe. Saitama faces off against him in a battle that further exemplifies Saitama's overwhelming power. Another reoccurring enemy in this volume is Speed O Sonic. He sees Saitama as a rival. A skilled ninja assassin, Sonic's incredible speed and combat abilities make him a formidable opponent. While not a major villain in this volume, his encounters with Saitama add a dynamic and humorous element to the story.
As Saitama's reputation grows and more powerful enemies emerge, the series delves into themes of heroism, the pursuit of challenges, and the consequences of overwhelming strength. With its unique blend of action, humor, and commentary on superhero tropes, "One Punch Man" Volume 3 continues to captivate readers and explore the limits of power and purpose in a world filled with chaos and monsters.