Doumu Shinjou is a 10-year-old boy whose father, a legendary deceased player for the Yomiuri Giants, passed down to him both a passion for baseball and remarkable skill, though his mother and older sister constantly urge him to quit the sport. Before his death, his father managed to teach him one final technique—a magic shot. When his mother gives him the glove his father used, Doumu executes this shot during a Giants training session and is immediately signed to the team. With the veteran players backing him, the Giants become invincible at home, as no major batter in the Japanese professional league can handle his magic shot. However, away games pose a challenge, since Doumu is only permitted to play at the Tokyo Dome, the stadium where his father was honored. Along his journey, new rivals emerge, alongside friends like Melody Norman, an American girl who disguises herself as a boy because women are barred from playing baseball. The Giants appear to be on the verge of winning the league title—until the arrival of the mysterious Don Carlos, a Spanish former bullfighter playing for the Hiroshima Toyo Carp, who seems to share a past with Doumu's father. Can Doumu lead the Giants to victory?