Growing up in a town without a little league team, Ishihama Bungo spent his days throwing a ball he was gifted against a wall. While Bungo is focused on the wall, he happens to encounter Noda Yukio, a member of the U-12 Japan Team! After their fateful meeting, they run into each other in middle school, both joining the super-powerhouse, Seio Senior. With their teammates, they aim to take Seio Senior to the top of middle school baseball, facing off against many strong opponents along the way, growing to the point where they finally win the national championship, becoming the best in Japan. Due to their outstanding performances, Bungo and Noda are recruited by many powerhouse high schools on exceptional offers, but they both choose to attend the same school, Ouka High School, promising to achieve the unprecedented -- five consecutive Koshien titles.