If they had silver alerts where Woody Grant lives (they don't), the signs would be flashing on the interstates every five minutes. The ornery, wispy-haired man, edging toward senility and played with beautiful, self-effacing economy by Bruce Dern, is constantly wandering off, adrift in his own befuddlement.

In Nebraska, Alexander Payne's gem of a film, the line between determination and dementia is fading, like ghosts of white paint down the middle of a potholed highway.

In truth, and in his own mind, Woody is on a mission: making his way from his home in Billings, Mont., to Lincoln, Neb., to pick up a check for $1 million. Woody received a letter in the mail from a magazine subscription service announcing the windfall. It says so right there in black-and-white. Has to be true.

Speaking of black-and-white, Payne - the director of The Descendants, Sideways, and three films set in this very same American heartland (About Schmidt, Election, and Citizen Ruth) - has shot Nebraska in the stark, crisp, high-contrast format. That snow-capped Paramount logo in black-and-white at the front of the film harks back to another era. Is this a throwback comedy, a vintage family melodrama?

No. But the premise of Nebraska, written by Bob Nelson, does call to mind one of Preston Sturges' '40s classics, Christmas in July, in which Dick Powell believes he's won a big contest, with a big check to go with it. He and his girlfriend (Ellen Drew) go on a buying spree, and his friends and neighbors want in on the action.

That happens to Woody in Nebraska, too: Once word gets out about his seven-figure surprise, the woodwork (and wood paneling) is acrawl with folks, one hand slapping Woody on the back in congratulations, the other open-palmed and hoping for a share.

Nebraska is not a breakneck, screwball farce - although it has its moments, like the comical heist of an air compressor from a farmer's barn. Payne's film is loping. It's deadpan, poignant, absurd. And it's a road movie, in which Woody's son, David (Will Forte), decides to let the old man have his fantasy - for at least as long as it takes to drive him to Lincoln. There are issues to work out between the father, recalcitrant, remote, and his boy, who works in an electronics shop and whose girlfriend has left him. Forte, the former Saturday Night Live trouper, has a stunned, mournful look to him - it's a terrifically quiet, nuanced turn.

And Dern? Who would have thunk that the wild veteran, full of kooky menace in westerns and Hitchcock, in Hollywood blockbusters and duds all through the second half of the 20th century, could pull off such an interior role? Well, Payne thunk it, for one, and the director gets a career-defining performance from his star. The pain and hope and sense of loss are all there in Dern's eyes, in Woody's stolid willfulness, his shaky gait.

Nebraska is wistful and a little bleak. The Great Recession hovers over the Plains and the people living there. But the film is also wonderfully funny and observant and filled with compassion for its characters - even the shifty ones (Stacy Keach, as an old business partner), and the nagging ones (June Squibb, as Woody's wife).

Woody's journey may not end the way he imagined it would, or wanted it to, but maybe he's not as lost as everybody thought. Turn the silver alerts off. The old-timer has been found.

Nebraska **** (Out of four stars)

Directed by Alexander Payne. With Bruce Dern, Will Forte, June Squibb, and Stacy Keach. Distributed by Paramount Vantage.

Running time: 1 hour, 55 mins.

Parent's guide: R (profanity, violence, adult themes)

Playing at: Ritz Five and Carmike at the Ritz Center/NJEndText