Inaba Naoya, who grew up abroad, admires Yankees because he was saved by one when he was a child. One day, he finally arrives in Japan to attend high school for one year. He chooses a run-down school that is full of delinquent (yankee-like) students. Soon, he realizes the importance of water polo to their school. He decides to rebuild the water polo club so that his classmates will finally have a purpose to focus on.