A wonderful adventure in a long forgotten land full of dinosaurs and cavemen as only Edgar Rice Burroughs can tell it. "Young Wilhelm von Horst had been given up for lost. His comrades in the expedition had sailed to the surface without him, mourning the loss of their friend. But von Horst had not died. His only companion a barbarian girl, he battles his way to safety through terrors inconceivable on the surface of the Earth." Cover painting by Frank Frazetta.