An aging, booze-addled man named Woody Grant is convinced he's won a million-dollar magazine sweepstakes. Woody's frequent attempts to walk from his home in Billings, Montana to claim his prize in Lincoln, Nebraska, are thwarted by his family and his own disorienting episodes of disorientation and stubbornness. His son, David, a down-on-his-luck electronics salesman, is roped into the delusion, reluctantly agreeing to drive his father to Nebraska. Along the way, David grapples with his father's past and present behavior; the journey offers a last chance to forge a connection despite Woody's fading faculties and the long shadows of an unfulfilled life.

As father and son hit the road, the trip through the stark Midwestern landscape becomes more than a mere pragmatic endeavor. It evolves into a path of discovery, dotted by impromptu detours, including an unscheduled stop in Woody's hometown of Hawthorne, Nebraska. There, the duo encounters family members and old friends, all of whom quickly learn of Woody's supposed fortune. These encounters lay bare family dynamics, exaggerate old grievances, and stir up envy, as people whom Woody has not seen in years suddenly take a keen interest in his "winnings". David observes the effect of the rumors about Woody's prize, gaining insight into his father's history, his parents' relationship, and the true nature of the bonds that hold families together.