Mr. Gu, who runs a bulgogi restaurant in a working-class village on the outskirts of Seoul, worries about his overweight son and decides to form a baseball team for the elementary school. Mr. Gu invites former baseball player Chu Nak-cheon to be the coach. Mr. Gu empties his safe to buy uniforms and equipment, and begins training, but the team lacks talent. One day, they play a friendly match against a prestigious school's baseball team and suffer a crushing defeat 20-0. Everyone is disappointed, and the baseball team is on the verge of disbandment, but coach Chu brings his son Seong-jin, raised by his ex-wife. They use the vacation for strenuous training, strengthening the team, and emerge as a new baseball team in the national tournament, reaching the semifinals before being eliminated. However, they shed hot tears, promising a next match.