About Schmidt opens with a postcard-like montage of shots of director Alexander Payne’s favorite city: Omaha. It’s a silent litany of desolate lots, empty streets, and tattered storefronts that ends on the towering eyesore of the Wood Man insurance building. Inside waits Warren Schmidt (Jack Nicholson in a consummate performance), who’s the saddest eyesore of all. He sits at his empty desk staring at the clock as it crawls to five — the moment when his career as an assistant vice-president will come to an end and his swollen, non-comprehending face (when did Nicholson turn into Ernest Borgnine?) will presumably explode.

You’d expect no less from Jack Nicholson, but this examination of futility, loss, and numb perseverance doesn’t offer the cathartic fireworks of, say, The Shining (an old fraternity photo of Schmidt does recall one of the more chilling moments of Kubrick’s underrated masterpiece). It does, however, provide a trip down memory lane that showcases some of the greatest hits of Nicholson’s career, from the dentally fixated masochist of Little Shop of Horrors (Schmidt contemplating the mixed horror and delight of a hot tub containing a nude Kathy Bates) to the justice-and-reason-obsessed ex-cop of The Pledge (Schmidt contemplating the mixed horror and despair of a tawdry retirement party). It may not be his best performance, but it is almost all of them.

That performance guides and — what’s ironic from such a flamboyant actor — moderates Payne’s own abbreviated tour of America as he ventures from his Nebraska stomping grounds and from the caustic but limited satire of his previous two features, Citizen Ruth (1996) and Election (1999). Payne not only sends his hero as far away as Kansas and Colorado but also pushes him into a confrontation with the void of mortality and the consolation of compassion.

Not that Schmidt needs the film’s frequent images of fresh meat and stockyard-bound livestock to remind him that his reward for a lifetime of conformity to the system is to be consumed by it. The morning after his farewell fête finds him awakening involuntarily at 7 a.m. to pore over a Jumble puzzle in his den. Later he will join his wife, Helen (June Squibb), for breakfast in the brand new Winnebago that’s parked in the driveway so they can get a taste of what their future life together will be like. Not very appetizing. The only glimpse of hope is a TV ad for Save the Children, and Schmidt finds himself sponsoring a tiny Tanzanian boy named Ndugu, sending him $22 a month and letters that are his sole outlet for rage, frustration, and fear. Recited in voiceover by Nicholson, they provide the film’s unreliable but utterly honest narration.

Schmidt’s complaints are many, though they’re couched in hilarious attempts at decorum. His distaste for his aging, controlling wife ("Who is this old woman who lives in my house?") is eclipsed by his disdain for Randall (Dermot Mulroney), the man his only child, Jeannie (Hope Davis), has chosen to marry. Unexpected circumstances compel him to assert himself one last time, and so he climbs into the Winnebago and heads out to Denver — with stops and detours along the way to reflect on his own and America’s past and future — to try to stop the wedding.

His journey recalls the one in David Lynch’s The Straight Story, and as in that film, Payne’s irony transcends parody and approaches the tragic. Of course, as in all of this director’s work, that irony is still pretty broad. Isn’t it enough to give Randall a mullet — must he have prematurely thinning hair and a Fu Manchu moustache and sell waterbeds, too? The women characters verge on misogynistic stereotype, as they might in any film that includes in its cast both Hope Davis and Kathy Bates. In the original Louis Begley novel, Schmidt was an urbane, white-shoe New York City lawyer whose intelligence and self-awareness flattered the reader’s sympathy. Here he’s is a schmuck; should we laugh or admit we might be one too?

But Schmidt is also Jack Nicholson, and there’s something about the way he intones the words "Dear Ndugu: I hope you’re sitting down when you read this . . . " that makes him, and us, both in on and the butt of the joke. Maybe no other actor, or director, could pull that off, or make the film’s concluding tear — shocking, mysterious, and inevitable — no laughing matter at all.