Not as bad as all that, but certainly not good – a Martian adventure full of aliens with indistinguishable-sounding names, overexplainy without making us understand or care. Could’ve taken a lesson on narrative clarity in unfamiliar worlds from Nausicaa.
Muscley Carter grumbles that he’ll fight for no cause, would rather be locked up by General Malcolm’s Dad than fight in his dirty Civil War. Carter finds a cave of gold, guarded by a bald dude who warps him to Mars, which he finds engulfed in a Civil War in which Carter grumbles he will not fight. But he meets a girl, so he fights for her instead with his amazing strength and jumping abilities, defeating McNutty, who receives orders from multidimensional bald super-alien Mark Strong (sad trailer-home sniper of Tinker Tailor, psycho-baddie of Sunshine).
Oh wait, there’s a simpering frame story in which young Edgar Rice Burroughs (Juni of Spy Kids) is supposed to inherit Carter’s fortune but is actually being entrusted to protect Carter’s body on Earth while his astral projection makes sweet love to a Martian princess. Bunch of people in the credits who I never saw turned out to play motion-capture aliens – bummer. See ya some other time, Samantha Morton and Willem Dafoe.