Edgar Rice Burroughs’s classic example of pulp science fiction, A Princess of Mars (1912), is considered to be one of the original inter-planetary romance novels, a trope that would continue throughout science fiction for decades to come. The book follows Confederate veteran John Carter after he is suddenly transported from a cave in Arizona to the planet Mars. Carter falls in with a gang of Martians called Tharks, and eventually wins the heart of Heliumite princess Dejah Thoris. A Princess of Mars is the first in Burroughs's Barsoom series, which includes eleven books in total. A Princess of Mars begins on Earth. American Civil War veteran John Carter and his friend and fellow Confederate soldier James Powell travel to Arizona to prospect for gold. John and James find a supply of gold in a cave that would make them wealthy for the rest of their lives; unfortunately, they are attacked by a group of Apache Indians before they can harvest the gold. Powell is killed by the Apaches, but Carter finds a second cave where he hides out to avoid being murdered. Inside the cave, Carter suddenly becomes drowsy. When he wakes up, he finds himself on Mars. On Mars, the much lighter gravity makes Carter super-strong; he uses his skill to his advantage when he meets a gang of skeptical, war-like Tharks. The Tharks are a tribe of six-armed Martians who frequently battle other tribes on Mars; Carter rapidly falls in with the gang because of his strength and his history in combat. During one particular conflict, the Tharks and their second-in-command Tar Tarkis lead an attack on a Heliumite tribe, whose actions they believe are dangerous to all Martians. Among the Heliumite tribe is human princess Dejah Thoris, who is captured by the Tharks. Dejah tries to explain that the Heliumites were trying to benefit all Martians with their convoy; her speech causes Carter to fall in love with her. Dejah's fate is threatened when the ruler of all Martians decides that she will be sacrificed for the great Martian games. Refusing to allow Dejah to be sacrificed, Carter goes into hiding with Dejah, his dog Woolah, and a Martian friend, Sola. While protecting Sola and Dejah, Carter is captured and thrown into Warhoon prison. In prison, he meets another human, a Heliumite like Dejah, named Kanto Kan. Kanto was part of a search party looking for Dejah; Carter tells Kanto that Dejah is safe, for now. The Warhoon's decide to pit Kanto and Carter against each other in a battle to the death, where the winner will be granted his freedom. Kanto and Carter game the system when Carter pretends to be dead, freeing Kanto and allowing Carter to escape when he is placed in a Warhoon morgue. Once the two men escape, they meet up again in the dangerous city of Zodanga, only to discover that while they were locked up, the Zodangans had attacked Helium. The Zodangans insist the attacks will only end when the beautiful Dejah marries the Zodangan prince Sab Than. As Carter and Kanto travel to save Helium and Dejah, Carter discovers that the Tharks are at war with the Warhoons, and briefly joins forces with them to help them overcome the war-mongering Warhoons. Tar Tarkis realizes during the conflict that Carter is a friend; after the Tharks achieve victory, they join forces with Carter to save Dejah and the Heliumites from Zodangan attack. With the Tharks by his side, Carter intervenes in the wedding between Dejah and Prince Sab Than, and during the aftermath of the fight, Dejah confesses her love for Carter. Ultimately, the Heliumites and the Martians establish an alliance, and Carter and Dejah get married, making Carter the new Prince of the Heliumites. The couple lives happily for nine years together until they discover that the Martian atmosphere factories are on the fritz and that soon the entire population of Mars will suffocate in the toxic atmosphere. Carter hurries to the Martian factory but passes out inside. When he wakes up, he is back in the cave in Arizona where he first discovered the gold.