It is decidedly not the most wonderful time of the year for Macy’s Christmas elf Crumpet. In fact, if you so much as look at him the wrong way, he’d invite you to stick that candy cane.

Crumpet, portrayed by Joe Brack, is the holiday alter-ego of bestselling humorist David Sedaris during his real-life stint as an elf for one grim Christmas season after failing to find work in the soap opera biz. The one-man show was adapted by Joe Mantello for the stage from Sedaris’ 1992 piece of the same name for the public-radio show This American Life.

Santaland is especially timely for this holiday season, with the unemployment rate hovering near 10 percent nationwide and scores of Americans willing to give their left arm for an unsavory job involving a humiliating costume. Caught in a past recession, while waiting to hear from the store after his interview, Sedaris notes that things could be worse: “[There is] the very real possibility that I will not get hired,” he says. “When you can’t get hired as an elf, you are a failure.”

Still, he notes, it’s better than handing out leaflets on a street corner, dressed as a taco. Sedaris leads us through the unique hell that he experienced as the lowest form of life in the holiday retail world, from bizarre corporate training rituals to helicopter parents to bodily fluids. He recounts the time that a little girl was having a tantrum, and he was asked by her mother to tell the child to behave or else Santa would bring her coal. “Santa no longer traffics in coal,” he told the girl. “Instead, if you’re bad, he comes to your house and steals your belongings.” Another day, Macy’s hosted a special event for deaf children, and the elves were taught to sign holiday phrases. With the help of his sister’s deaf neighbor, Sedaris took some extracurricular lessons to learn how to sign “Santa has a tumor in his brain the size of an olive.”

Brack’s energetic portrayal of Crumpet is remarkable in his ability to simultaneously convey self-contempt and near-sociopathic glee. In fact, when describing some of the most unsavory elements of the job, Brack achieves a manic facial expression that precisely emulates that of Jack Nicholson in the “Heeeeree’s Johnny!” scene of The Shining—an extra-special accomplishment for a holiday play. He also interacts with the audience in the first-row seats, to their great amusement and discomfort, even pulling this reporter onto the stage for an impromptu dance, followed by a curt dismissal.

The Christmas grump has long been an archetype in our culture, from Scrooge to the Grinch to George Bailey, and the traditional plot arc follows his subsequent reform as a man who always keeps Christmas in his heart. Sedaris’ Diaries is no different—after all, how could a holiday play end on a note that doesn’t bring glad tidings? Nevertheless, those who have followed the author’s career know that the effect was short-lived. Six books later, he’s still the self-involved curmudgeon that we know and love from his essays and stints on NPR. But after one synthetic snow-covered month, the foul-mouthed, cynical Christmas elf ends up getting a generous dose of what he gave out so sparingly: holiday cheer.

Santaland Diaries, directed by Matty Griffiths and Alexander Fernandez, written by David Sedaris and adapted by Joe Mantello, Produced by City Artistic Partnerships and the Warehouse Theater. At the Warehouse, 643 New York Ave. NW., to Dec. 24. $15.