As this final volume of The Berrybender Narratives opens, Tasmin and her family are under irksome, though comfortable, arrest in Mexican Santa Fe. Her father, the eccentric Lord Berrybender, is planning to head for Texas with his whole family and his retainers. Tasmin, who would once have followed her husband, Jim Snow, anywhere, is no longer even sure she likes him, or knows where to go to next.

In the meantime, Jim Snow, accompanied by Kit Carson, journeys to New Orleans, where he meets up with a muscular black giant named Juppy in whose company they make their way back to Santa Fe. But even they are unable to prevent the Mexicans from carrying the Berrybender family on a long and terrible journey across the desert to Vera Cruz.

Starving, dying of thirst, and in constant, bloody battle with slavers pursuing them, the Berrybenders finally make their way to civilization, where Jim Snow has to choose between Tasmin and the great American plains, on which he has lived all his life in freedom, and where, after all her adventures, Tasmin must finally decide where her future lies.

With a cast of characters that includes almost every major real-life figure of the West, Folly and Glory is a novel that represents the culmination of a great and unique four-volume saga of the early days of the West; it is one of Larry McMurtry's finest achievements.