Tara of Helium, John Carter's second child, is nearly as beautiful as her mother, Deja Thoris, and as independent-minded as her father. These qualities cause her much grief during a long series of imprisonments by hostile aliens. She is aided by a rejected suitor whom she fails to recognize but gradually learns first to trust and then to love, despite what she imagines to be a hopeless chasm between their social classes. A highly evolved race of intelligent beings is discovered in this novel, one of whom forms with Tara a complicated relationship that opens his eyes to the value of certain aspects of life which he and his kind have shed. We also learn of an ancient Martian culture differing markedly from the technologically advanced civilizations of other city-states; one of its pastimes is a bloody variation of Martian chess, played with human beings as the game pieces. For variety of character and incident, this novel is unsurpassed by its four predecessors in the series.