Fifteen-year-old Marvin is a social outcast: a street rat, an orphan, a rebel. He lives in Mr. O's junkyard in the town of Upper Squares, where the rich get richer, the power-hungry get more powerful, and laws are written to try to get rid of the poor and needy for good. But Marvin has had enough. When he, with the support of his mangy, orphaned friends, manages to join a socially elite baseball team, Marvin meets his adversary-coach Boyd Lakes. Boyd is one of the most power-hungry of them all, and he wants nothing to do with Marvin. He and the other players on the team consider Marvin to be a disease on the team that must be eliminated. Boyd pushes Marvin to his limits, trying to get him to quit, but Marvin refuses to give up. Mustering all his courage, he continues to show up and leave it all on the field. Though at times he is tempted to walk away, he knows that his place on the team is about much more than baseball. Soon, his skills, sportsmanship, and indomitable spirit catch the attention of hundreds of people in the Upper Squares community, all of who begin to root for the underdog. He suddenly finds himself front and center, standing in the spotlight of the authorities that abandoned him to the streets. By the time the final game of the season rolls around, Marvin is in the midst of a political firestorm-and he realizes this is his one chance to change everything, once and for all.