Carter is an American Civil War veteran who goes to sleep in a cave after being chased by Apache Indians and wakes up on Mars, here called Barsoom. Formerly an Earthlike world, it became less hospitable to life due to its advanced age: as the oceans evaporated, and the atmosphere thinned, the planet devolved into partial barbarism with the inhabitants hardened and warlike, fighting one another to survive. Barsoomians distribute scarce water supplies via a worldwide system of canals, controlled by quarreling city-states. The Martian atmosphere is maintained by a power plant. Carter rescues a humanoid Red Martian princess, Dejah Thoris, from the belligerent four-armed Green Martians, whose respect he gains for his superior strength and fighting ability. He enlists the Green Martians’ assistance in winning a civil war, and saves Mars from destruction when its atmosphere plant malfunctions.
John Carter Of Mars hits theaters on June 8, 2012 directed by Andrew Stanton and starring Taylor Kitsch, Lynn Collins, Samantha Morton, Mark Strong, Ciaran Hinds, Dominic West, James Purefoy, Daryl Sabara, Polly Walker, Bryan Cranston, Thomas Hayden Church, and Willem Dafoe.