During the holiday season Americans feel the senseless compulsion to raid shopping malls like bands of toy-obsessed pirates. Yet they never stop to wonder what it might be like to be constantly immersed in the dollar-bill green cheer of American Christmas.

Based on an essay by David Sedaris and adapted for the stage by Joe Mantello, “The Santaland Diaries” at the Long Wharf begins with a man (Thomas Sadoski) standing in front of a gift-wrapped stage, relating how he’d laughed when he first saw a help wanted ad for Christmas elves at Macy’s. He goes on, in a tone of disbelieving horror, to tell us how he applied, got the job and passed the mandatory training classes to work at the mall’s Santaland. He dons his uniform on stage — complete with cap, shoes and black stomach pillow — as an expression of maniacal, masochistic glee spreads across his face. A shimmering figure of chartreuse and green, the man now known as Crumpet continues with the tragic story of a position that is easily the most humiliating ever conceived by the human race.

Though it’s entertaining, “Santaland” often has the feel of premeditated stand-up comedy. The entire plot consists of a single monologue, a construction that removes some of theater’s dynamic potential: The audience is certain that no character will suddenly rush on to the scene, that there will be no theatrical surprises in the play, only rhetorical ones. “Santaland” is, therefore, not so much theater as a lively and often uproarious speech that unfortunately adds little to the poignancy of Sedaris’ writing.

Sadoski’s delivery occasionally further increases the artificiality, acquiring a tone that seems slightly too stilted for his character. However, he often lapses into a colloquial and personal style that is reminiscent of a friend telling a bizarre story over dinner. Those moments, which occur consistently at the monologue’s more significant sections, reveal the potential warmth and intensity possible in this dramatic format.

At moments the satire is almost terrifying, revealing the phantom of racism and chauvinism that persist in a modern New York. Two of the Santas in Macy’s are black and, realizing this, some of the shoppers express a preference. “White,” one woman mutters to Crumpet, “white like us.” Though we laugh at the elf’s decision to do the opposite of what she asks, we cannot laugh at the comment itself. Unlike blind consumerism, into which every American openly hurls himself with feral zeal, racism is not something that we are willing to see in ourselves — or even in those with whom we share our shopping malls. Here Sedaris deals not with harmless human eccentricity, but a basic fact of dark and ignorant human nature.

Spouting numerous and rapid caricatures of the hapless shoppers that Christmas Eve found at Santaland, Sadoski reaches a moment at which his story staggers on the edge of believability. But the monologue suddenly slows, and what could have easily followed the logical progression of yuletide cynicism topples in exactly the opposite direction. Snow begins to fall, and the first signs of unembittered human emotion appear on the elf’s face. The result is somewhat discomfiting: The audience member cringes, expecting Crumpet to look beatifically to the rafters and lisp, “And that, Charlie Brown, is what Christmas is all about.” Alternatively some child or baby animal could be crushed in the consumerist fray (a death that Sedaris would have certainly exploited). We are spared such a extremely saccharine or melodramatic conclusion and left with something more subtle but in the same spirit. The play’s biting last line recovers it from fluffy sentimentality.

As an acerbic indictment of America’s obsessive love of Santa, “Santaland” ultimately succeeds. But it probably would be better and more fitting to spend a simpler, quieter night reading Sedaris’ essay, removed from the expensive and ultimately unnecessary sparkle of professional theater.