Saburo, a high school student with athletic prowess but struggling academically, unexpectedly finds himself transported back to the year 1549 during the Sengoku era. In this historical setting, he encounters Nobunaga Oda, a young man who bears an uncanny resemblance to him. Nobunaga, the son of a powerful warlord and the magistrate of the lower Owari Province, is physically frail and requests Saburo to assume his identity. Accepting the challenge, Saburo steps into Nobunaga’s role and embarks on a mission to unify Japan.