In 1945, the United States is a Jim Crow nation. Jim Crow was a character in an old racist song, and his name has come to stand for segregation. In the South, everything is segregated: schools, buses, restaurants, hotels, theaters, restrooms, water fountains, even phone booths . The rest of the country isn't as blatant about it, but separation and prejudice exist there too. And when it comes to the national pastime—baseball— there are the major leagues, the minor leagues, and there are separate Negro leagues, for ballplayers of color. White major leaguers play in fine ballparks, travel first class, and sleep in decent hotels. Negro leaguers have no ballparks of their own, and usually get lower pay. Equipment is shabby, the travel brutal, and blacks almost always have trouble finding hotel rooms or restaurants.

One white man who understands how wrong it is to keep baseball segregated is Branch Rickey , general manager of the Brooklyn Dodgers. He decides he is going to change baseball. He knows it won't be easy. Fighting prejudice never is. But he is a shrewd businessman. He knows that black ballplayers are a pool of inexpensive talent, and that they play an exciting, hustling kind of baseball. Rickey knows they will bring a new audience to the majors. Later he says, "I was convinced that there was a timelessness about it. After waiting a hundred years, these people were legally free, not spiritually free, never morally free. And I felt that if the right man ... with ability on the field and with control of himself off the field, if I could find that kind of a man, the American public would accept him."