Splotches of brown mottle metallic girders on the set of “The Full Monty,” the latest offering from the Keegan Theatre. The allusion to rust is apt enough: David Yazbek and Terrence McNally’s Broadway-tested musical spins a tale of the Rust Belt — specifically, Buffalo, N.Y., in the late 1990s. The principal characters are blue-collar guys who have been laid off from local industry: Deprived of the jobs that once oriented their lives and fed their self-esteem, they feel, at least at the start of this determinedly frisky story, that they are watching a world order corrode.

It’s too bad the Keegan production itself feels as languishing as the socioeconomic reality it portrays: With the exception of a couple of sequences, and one or two supporting performances, this “Full Monty” is stiff, stilted and halting. Co-directors Mark A. Rhea and Susan Marie Rhea have wholly failed to give the scenes sufficient flow, and they have tolerated conversational and transitional pauses that distend the running time egregiously. The actors often look ill at ease; the singing tends to range between adequate and shaky. Even the scenic projections — caught on screens framed by those girders — look washed-out.

The projections — a cityscape, a park vista, and more — evoke the home turf of Jerry (Kurt Boehm), an erstwhile steelworker whose marriage has crumbled. Desperate to earn cash for child-support payments, Jerry conceives of mounting a Chippendales-style striptease act: He and a few other unemployed guys will disrobe onstage and reap a financial bonanza.

Needless to say, the scheme proves tricky to execute — not least because Jerry and his would-be cast-mates lack confidence and showbiz know-how. As the Keegan production plods along, the cast often seems to share the characters’ plight: Frequently positioned in artificial-looking tableaux, the actors — including Matthew Dewberry as Jerry’s best friend; and Charlie Abel as a former mill supervisor — exude an air of hard-working discomfiture.

There are, admittedly, a couple of exceptions. In the show’s only truly enjoyable scene, an elderly character named Horse auditions for the striptease act, letting rip with a heartfelt song and dance, insofar as his arthritis will permit. Patrick Doneghy plays Horse here, and when he launches into the Funky Chicken and other bits of exuberant, unrefined hoofin’, the entire production seems to light up.

The sequence is all too brief, alas, in a production that — including a marathon intermission doubtless made necessary by the long restroom line — clocked in at three hours and 15 minutes at the reviewed performance. (Keegan is raising money to renovate the Church Street Theater.)

In other turns worthy of mention, Rena Cherry Brown is poised and hilarious as a gravelly-voiced pianist. And Priscilla Cuellar and Kari Ginsburg, who play intelligent, supportive wives, do some assured, melodious singing.

Occasionally an ensemble number almost breaks free of the production’s malaise: The song “The Goods” — in which Jerry and his pals imagine that their act has earned the scorn of Buffalo’s ladies — has some pleasantly sassy, hip-shaking, finger-wagging moments. (Ashleigh King supplied the show’s businesslike choreography.)

Also on a sort-of positive note: The climactic reveal is subtly lit.

Celia Wren is a freelance writer.

The Full Monty

music and lyrics by David Yazbek; book by Terrence McNally. Directed by Mark A. Rhea and Susan Marie Rhea; musical direction and sound design, Jake Null; set design, 4Point Design Collective; costume design, Erin Nugent; lighting, Allan Sean Weeks; properties, Carol Floretta H. Baker; hair and makeup, Craig Miller; assistant director, Colin Smith. With John Loughney, Michael Innocenti, Max Jackson, Autumn Seavey Hicks, Josh Sticklin and others. Three hours or more. Through June 8 at the Church Street Theater, 1742 Church Street NW, Washington, D.C. Call 703-892-0202 or visit www.keegantheatre.com.