Edgar Rice Burroughs returns to Barsoom and his eternal hero, John Carter for four more thrilling adventures in Llana of Gathol. In "The Ancient Dead" John Carter is cast into the catacombs underneath the inpregnable citadel of Horz. There he discovers his granddaughter, Llana of Gathol, stranded there after escaping abduction. Next, Carter, Llana, and friends are captured by the "Black Pirates of Barsoom". As slaves controlled by a diabolical machine, Carter must fight to survive and free his friends. In "Escape on Mars", Carter and friends are shot down by a mysterious ship. Carter is rescued by the Panars, but his friends disappear. He tracks Llana to the inescapable city of Pankar. It will take all his talents to rescue her. Finally, "The Invisible Men of Mars" make their debut as Carter and Llana escape Pankar. John Carter will have yet another princess of Mars on his hands and have to wage war before he can return to his wife back in Helium.