Publisher's Synopsis
After John Carter's arrival, a boat of Green Martians arrive on the River Iss and are ambushed by the previously unknown Plant Men. The lone survivor is his friend Tars Tarkas, the Jeddak of Thark, who has taken the pilgrimage to the Valley Dor to find Carter.
Carter and Tars Tarkas discover that the Therns, rulers of Valley Dor, a white-skinned race of self-proclaimed gods, have for eons deceived the Barsoomians of the outer world by disseminating the myth that the pilgrimage to the Valley Dor is a journey to paradise. Most arrivals are killed by the beasts of Valley, the survivors enslaved by Therns. Carter and Tars Tarkas rescue Thuvia, a slave girl, and attempt to escape, capitalizing on the confusion caused by an attack by the Black Pirates of Barsoom upon the Therns. They are separated during the attack: Tars Tarkas and Thuvia hijack a Black Pirate flier, while Carter fights his way aboard another, killing all but one of the Pirates, and rescuing a captive Thern princess. Carter, talking with the captured Pirate Xodar, discovers that the Black Pirates, called the "First Born", also think of themselves as gods, and prey upon the Therns as the Therns prey upon others. He also discovers that the captive Thern is Phaidor, daughter of the "Holy Hekkador" (high priest) of the Therns. When their flier is recaptured by the First Born, they are taken to their land, built around the underground sea of Omean, below the lost sea of Korus and the Valley Dor. Both are located at the South Pole of Barsoom.
