Like many high school students, Kotaro Mochizuki (Haruma Miura) doesn't find life easy. His mother nags him to study harder and get into a good university. High achieving scholars and popular athletes outshine him at school. Mochizuki laments that he is just another loser. But Mochizuki does have a heart. He can't bear to see his pathologically bumbling and shy classmate Tsuyoshi Nakamura (Yuu Shirota) playing into the hands of the bullies. Being clumsy and timid himself, however, Mochizuki can't do much to defend Nakamura.

That is until he discovers that he has magical samurai powers. After reading a book that describes historic, heroic feats of a warrior samurai who shares his name, Mochizuki finds that in a pinch, a samurai spirit and strength overtake his body, elevating him into a fearless fighter who spews forth pearls of wisdom of the "bushido" or "code of the samurai."

The comedy drama is based on serious issues in the school yard such as inequality, discrimination, harassment and bullying, but presents them in a light-hearted manner through exaggerated characters and grandiose actions. The fantastical transformation of Mochizuki from awkward student to valiant samurai is both humorous and cathartic and will thrill audiences, especially those who have been secretly yearning for their chance for payback.