Jackie Robinson, Major League Baseball's first African-American player, was still a member of the Brooklyn Dodgers when this movie was made.
After winning over his teammates and fans, Jackie Robinson leads the Brooklyn Dodgers to the 1947 National League pennant and wins the Rookie of the Year award. After Branch Rickey tells him he doesn't need to be silent anymore, Jackie speaks in front of Congress about civil rights and becomes involved in the Civil Rights movement.
The movie starts in 1928, with a young Jackie Robinson playing baseball without a glove with a group of kids. The coach of that team gives Jackie and old beat-up glove, and that is where his love of baseball begins. Years later, Jackie (playing himself) has made a name for himself as a multi-sport star, first at Pasadena Junior College (where he breaks his brother's long jump record), then at UCLA. At UCLA, Jackie plays football, basketball, track, and baseball, which he considers his best sport. As he nears graduation, he knows that his pro prospects are few, and all of his requests to coach in high school or college are turned down because of his skin color. He worries that he will be just like his brother Mack. Mack was also a multi-sport star and college graduate, but the only job he could get was that of a street cleaner. Those worries change once Jackie gets drafted into the US Army, where he serves as an athletic director.
After his stint in the Army ends, Jackie goes back to looking for a job as a coach, but with no luck. He does get an offer to play with a Negro League team, but he is hesitant because the constant travel will keep him away from his college sweetheart Rae (Ruby Dee). She encourages him to go, so he agrees to join the team. While playing, he catches the eye of a scout for the Brooklyn Dodgers, who wants to take him to see the team's president, Branch Rickey (Minor Watson). Convinced that the offer is legitimate, Jackie meets Rickey, who tells him that the Dodgers have been looking to add black players for a while, but were looking for the right person. Rickey knows that Jackie has the athletic ability, but does he have what it takes to endure the constant harassment he will face? Will he have the guts not to fight back? Jackie says he does, and the Dodgers sign him to play for their minor league team in Montreal, but with a condition. Jackie has to remain quiet and turn the other cheek when confronted by irate fans or opponents, or the experiment of blacks in Major League Baseball will fail and not be tried again for decades. Knowing the difficult times he will face, Jackie wants to protect Rae and delay getting married, but she wants to be by his side to support him, so they get married.
Jackie reports to Montreal, where his new teammates are reluctant to include him in their activities. Their manager is skeptical that a black man can succeed in a white man's game, but Branch Rickey tells him to give Jackie a chance. When Jackie has a great start to the season, his teammates begin to support him, and his manager sees that he is a good player. As the season progresses, Jackie endures the booing and name-calling from the fans and opponents, but also leads the league in hitting. At the end of the season, Jackie helps Montreal win the minor league World Series. Rickey decides it's time to bring Jackie to the Dodgers, but afterwards learns that several of the Dodgers players refuse to play with a black man. Rickey chastises the players for not allowing Jackie the chance to live his dream of playing professional baseball, and they will either have to deal with him as a teammate or they will be traded.
Jackie makes his debut with the Dodgers in 1947, but things aren't going well for him. Playing first base for the first time (he played second base in the Negro League and at Montreal), he makes several errors and is in a hitting slump. The harassment from the fans and the players for both the opponents and his own team aren't helping either. But with determination, Jackie is able to break out of the slump and also starts playing better at first base, which wins over his teammates and their fans.
At season's end, Jackie leads the Dodgers to the National League pennant and he wins the Rookie of the Year award. Jackie has also received a letter from the US Congress to speak about civil rights. Jackie goes to Branch Rickey and asks him what he should do. Rickey tells Jackie that he has been silent long enough and it's time to start speaking his mind.
The movie ends with Jackie speaking before Congress about the need for civil rights for blacks, and Jackie becomes a part of the Civil Rights movement.