
The British trio join Taylor Kitsch, Lynn Collins and Willem Dafoe in the film based on Edgar Rice Burroughs's science fiction pulp series, which revolves around a Civil War veteran who gets transported to Mars.
Morton will play Sola, the daughter of Dafoe's Martian warrior Tars Tarkas; West a prince called Sab Tham, who believes it is his right to rule Mars; and Walker is Sarkoja, an evil member of the Thark race.
'Wall-E' director Andrew Stanton expects 'John Carter Of Mars' an early 2010 production start for the film.