Before the wicked Issus, goddess of Barsoom, was destroyed and the people of Mars liberated from her fearful clutches, she imprisoned the princess Dejah Thoris in a pit which opens only once every year. But the princess is not alone: trapped with her is Thuvia, daughter of the King of Ptarth, and Phaidor, daughter of the great and wicked Holy Hekkador Matai Shang.Matai Shang employs the help of the only one who knows the secret to opening the pit in order to save his daughter. But, he absconds with the other two captives as well, leading John Carter on a mission which will unite all the nations of Barsoom’s north into a great confederation, with John Carter as their leader and Warlord of Mars.