Dreamgirls is a musical based on the show business aspirations and successes of acts such as The Supremes, The Shirelles and James Brown. A young female singing trio from Chicago get their big break at an amateur competition and begin singing backup vocals for James "Thunder" Early. However, things begin to spin out of control when their agent, Curtis Taylor, Jr., makes Deena and not Effie, the star of what will become known as "The Dreams."