Martian Child certainly isn’t much fun, unless you were desperately awaiting K-PAX with a kid instead of Kevin Spacey. Not that there’s ever any question whether Dennis (Bobby Coleman) is actually a Martian, but the conceit’s more or less the same: The kid sports sunglasses, lest the sunlight melt his eyeballs; builds elaborate contraptions meant to connect him with his home planet; and spends his time conducting field research before the aliens return to spirit him back to Mars. A sci-fi writer who knows nothing about being a father, John Cusack’s David Gordon adopts Dennis and believes his own experiences as a boyhood outsider will allow him to heal the wounded child. But Cusack and Coleman feel like they’re in two separate movies—Cusack in the one about the single dad trying to get his shit together, Coleman in the one about the strange boy who steals things and hangs upside down. Theirs is less a connection than a forced living arrangement brokered by agents and studio bosses.