Carter. Carter, Dejah, and Tarkas's daughter, Sola, reach a spot in a sacred river to find a way for Carter to get back to Earth. They discover that the medallions are powered by a "ninth ray" that is also the source of Sab Than's weapon. They are then attacked by a vicious race called the Warhoon under the direction of Shang. Carter and Dejah are taken back to Zodanga. A demoralized Dejah grudgingly agrees to marry Sab Than and gives Carter instructions on how to use the medallion to return to Earth. Carter decides to stay and is captured by Shang, who explains to him the purpose of Therns and how they manipulate the civilizations of different worlds to their doom, feeding off the planet's resources in the process, and intend to do the same thing with Barsoom by choosing Sab Than to rule the planet. Carter goes back to the Tharks with Sola to request their help. There they discover Tarkas has been overthrown by a ruthless brute, Tal Hajus. Carter and an injured Tarkas battle with two enormous Great White-Apes in an arena before Carter kills Hajus, thereby becoming the leader of the Tharks. The Thark army charges on Helium and defeats the Zodangan army, while Sab Than is killed and Shang is forced to escape. Carter becomes prince of Helium by marrying Dejah. On their first night, Carter decides to stay forever on Mars and throws away his medallion. Seizing this opportunity, Shang briefly reappears and gives Carter another challenge, sending him back to Earth. Carter embarks on a long quest to find one of their medallions on Earth; after several years he appears to die suddenly and asks for unusual funeral arrangements — consistent with his having found a medallion, since his return to Mars would leave his Earth body in a coma-like state, and makes Burroughs his protector. Back in the present, Burroughs runs back to Carter's tomb and uses clues to open it. Just as he does so, a Thern appears and raises a weapon before Carter appears and shoots the Thern in the back. He reveals that he had never found another medallion; instead, he devised a scheme to lure a Thern from hiding, thus winning Shang's challenge. Carter then uses the dead Thern's medallion to return to Barsoom. Cast Taylor Kitsch as John Carter, a Confederate army captain who is transported to