Great Horse was a wild horse of the forest in the days of the Cro-Magnons. And Tergo, son of the chief of the tribe, is the first man to ride a wild horse, through a chance accident, and with his grandfather's help, he uses this newfound experience to build up superstitious fear in the minds of his fellows. A story of adventure in pre-historic days; possibly a bit overcrowded and occasionally confusing as the author follows first Tergo's story, then the story of his little friend, Mishta. One could wish that the background had been played up more convincingly. It is often lost sight of in the succession of incidents. But it is a good yarn.