In a small town during the tumultuous Sengoku period in Japan, nine young, naive samurai believe that their clan's superintendent, Mutsuta, is corrupt. They plot to reform their clan and seek the counsel of a highly regarded chamberlain; however, they inadvertently involve themselves in a political trap. A cynical and unkempt ronin, overhearing their misguided plans to eliminate the superintendent, intervenes. After revealing his rough wisdom and strategic insight, he deduces the truth: the supposedly corrupt Mutsuta is actually the innocent victim of a conspiracy, and the chamberlain is the true villain, planning a coup to take over the clan.

The wandering ronin, against his better judgment, agrees to help the idealistic but inexperienced samurai foil the chamberlain's plot. Adopting the alias "Sanjūrō Tsubaki," which means "30-years-old Camellia," he skillfully manipulates events from behind the scenes, utilizing his wits to outsmart opponents and guide his young compatriots to the right course of action. "Sanjūrō's" unorthodox methods and jaded view of bushido (the samurai code) frequently befuddle the young samurai, leading to situational comedy and lessons in practicality and honor. While orchestrating a complex plan to rescue Mutsuta from his captors, "Sanjūrō" must navigate the treacherous waters of clan politics and human folly, threading a path between right and wrong, deception and integrity.