All 12 episodes from the Japanese anime based on Yusuke Murata´s manga remake of the web comic by ONE. Having gone through a rigorous training programme for three years, which resulted in the loss of his hair, the unassuming Saitama (voice of Makoto Furukawa) has become the ultimate superhero, capable of defeating his opponents with a single blow. However, Saitama has become jaded by the lack of effort needed to defeat his foes and performs his heroic duties with little vitality.
A young cyborg named Genos (Kaito Ishikawa) approaches Saitama looking for guidance in how to become stronger and when Saitama agrees to mentor him the pair embark on a quest to fight for justice.