After combat in Vietnam, African-American Robert Jackson returns home to Detroit in 1967 to discover racial unrest. His family reunion sours when he realizes his younger brother, Marcus, has joined a radical group fighting for civil rights. Meanwhile, rookie cop Thomas Riley is pounding his beat, maintaining family traditions, and trying to come to terms with the police department's rampant racism and brutality. Riley's and Jackson's paths inevitably collide when Marcus is murdered under circumstances that suggest the fatal shot was fired by the police and without justification. Jackson instantly turns radical himself and sets out to find the truth about his brother's death.