In a brilliant rejoinder and an inspired act of literary invention, Alice Randall explodes the world created in Margaret Mitchell's famous 1936 novel, the work that more than any other has defined our image of the antebellum South. Imagine simply that the black characters peopling that world were completely different, not egregious, one-dimensional stereotypes but fully alive, complex human beings. And then imagine, quite plausibly, that at the center...