When Rosa Parks defiantly refuses to take a back seat, she sets into motion a tumultuous string of events centered around the 1955 bus boycott in Montgomery, Ala. Using archival footage to establish the strained atmosphere of the era, this dramatization of that chapter of the Civil Rights Movement's history shows her interactions with such major figures as Dr. Martin Luther King Jr. (Jeffrey Wright), Coretta Scott King (Carmen Ejogo) and Ralph Abernathy (Terrence Howard).