Not-So-Jolly Rancher: Thornton battles the feds on his way to liftoff.

A lone man cannot build a rocket, launch himself into space, orbit the Earth, and then land safely somewhere near his Texas ranch. That should go without saying, but the impossibility of a one-person space program is sidestepped in this weirdly earnest fable, whose detachment from reality borders on the schizophrenic. The previous credits of writer-­director Michael Polish and co-writer (and twin brother) Mark Polish include such self-consciously offbeat flicks as Twin Falls Idaho, which at least had a sense of its own absurdity. This movie, whose lurching narrative suggests a panicky last-minute edit, is fully committed to its hoary Hollywood refrain: “If we don’t have our dreams, we have nothing,” would-be space jockey Charles Farmer (Billy Bob Thornton) tells the suits from the FBI, FAA, and other useless federal agencies that want to stop his liftoff. He ribs the feds about their failure to find WMDs, his lawyer denounces the way the Patriot Act has “twisted the laws,” and he borrows the “potted plant” line from Oliver North’s Iran-Contra attorney. But the important struggle is at home, where Farmer tries to sustain his family as the impending foreclosure of his ranch—bankers suck, too!—­interrupts his goal of blasting into space. (Never mind feeding the cattle.) Even Farmer’s pathologically supportive wife (Virginia Madsen) begins to waver, although the couple’s teenage son and two TV-commercial-cute daughters never do. If the movie were at least partially satirical, its implausibilities wouldn’t nag. But it isn’t, and they do. When Farmer scrambles for cash, why doesn’t he make a deal with the Discovery Channel or call Richard Branson? When he takes the kids out of school so they can help with the rocket, what exactly do they do? And when he finally does get into orbit, why does he open his helmet as if he were not in a ’60s-style space capsule but in, well, a movie studio somewhere? When The Astronaut Farmer counsels viewers to dream, what it really wants them to do is unplug their brains.