The Gateway Dinner Theater, although very much in the business of putting on plays, also seems to have modeled its operation after those all-American theme parks that try to provide something for every member of the all-American family.

The chief draw of the current package is a revival of a 19th-century melodrama, "Dirty Work at the Crossroads," but it is by no means the sole attraction. During dinner, a strolling banjo player plunks out tunes to masticate by. Once the patrons have moved into the theater, a couple of silent movies are unreeled. Then, the cast members bound on stage to introduce themselves, explain the mechanics of melodrama (hissing, we're assured, is welcomed) and to cajole everyone into a little group sing-along.

No sooner has the play itself unfolded than the youthful cast is right back on stage for a red-white-and-blue tribute to America, which includes tap-dancing to "I'm a Yankee Doodle Dandy," the singing of "Shenandoah" and "Dixie" and the unfurling of a 30-foot flag. Short of playing taps and distributing free soap samples, one wonders what else the management could do to curry favor.

There's nothing wrong with wanting to be liked, of course, but one suspects in the Gateway's case that it has no higher theatrical ambitions in mind. The evening is marked by an unrelenting air of cheerfulness, not unlike the smile on a Miss America contestant. It may not be fraudulent, but it is occasionally tiring.

"Dirty Work" is a typical mustache-twirler that puts its blond heroine and its square-jawed hero through all manner of turmoil and anguish, most of it engineered by a fortune-hunting villain who's after 1) the heroine's virtue, and 2) the mortgage to the farm. James Fouchard has designed the spiffy crossroads set that looks as if it had been cut from a patchwork quilt, and director Roger Meersman keeps the crises, not to mention an on-stage locomotive, coming thick and fast.

Not all of the youthful performers are comfortable playing melodrama, which requires a tricky double optic -- complete preposterousness of effect, coupled with abject honesty. But two of the actors are right on the beam. Bubba Garner, as the hayseed with a cowlick, makes a corny role perfectly delectable, while Peggy Henry contributes a grand comic turn as an upper-crust matron, whose crust barely hides her dipsomania.

The others are not quite so sure-footed, but they have buckets of energy and the kind of squeaky-clean appeal that seems to characterize the evening as a whole. "Dirty Work at the Crossroads" is not something you'd ever take your Village friends to see. But Aunt Em and Uncle Jeb might enjoy it as part of their Washington visit. Sandwiched, say, between the Air and Space Museum and a climb to the top of the Washington Monument.

DIRTY WORK AT THE CROSSROADS, by Bill Johnson; directed by Roger Meersman; choreography by James Walters; musical direction by Ron Tymus; technical direction by Clayton Cox; scenery by James Fouchard; costumes by Lynn Broderick; lighting by Ken Lewis. With Robert Redlinger, Bubba Garner, Sharon Ammen, John Corcoran, Peggy Henry, Mary Corcoran, Nanette Savard.

At the Gateway Dinner Theater, Wednesday through Sunday until Jan. 3.