The movie is about Minami Kawashima, a high school girl who becomes the manager of her school's baseball team in place of her hospitalized friend, Yuki Miyata. She tries to lead the team to the National High School Baseball Championship by learning strategies from the business book Management: Tasks, Responsibilities, Practices by Peter Drucker, which she mistakenly bought.

Minami joins her High School baseball team as a team manager after finding out that her best friend Yuuki is in the hospital and can't be a team manager any more. In order to try to fill in for Yuuki and to help out the team the best she can, she goes out to find a book on how to manage a baseball team. Unfortunately, she accidentally buys Peter Drucker's book called "Management: Tasks, Responsibilities, Practices" which is actually about how to properly manage a business. Because she couldn't return the book, she decides to read it anyway and to try to apply the business management concepts to the baseball team so that way they can go on and win the Nationals.