The delightful surprise of the Joffrey Ballet's opening appearance at the Kennedy Center Opera House last night was a relatively unfamiliar work by Antony Tudor, a gorgeous bit of fluff called "Offenbach in the Underworld," set to the tunefully racy score "Gaite' Parisienne" by the composer named in the title (in an arrangement by George Crum).

Even a minor ballet by a true master has a way of announcing the genius of its authorship, in its unfaltering craftsmanship and imaginative fecundity. In this case, Tudor's authority and inspiration--even in a lighthearted entertainment that pretends to no greater significance than the slender genre piece it is--was sufficient to redeem an otherwise anemic program, and indeed, to lift it to a peak of tickling ebullience.

As it happens, the ballet shows off the Joffrey troupe to particular advantage, playing, so to speak, to the company's strengths and averting its weaker sides. The dancers return the favor by performing the piece with a full measure of gusto and theatrical sparkle, without ever resorting to overstatement or burlesque.

"Offenbach in the Underworld" was originally choreographed in 1954 for a Philadelphia troupe, but Tudor revised it into the present version the following year for the National Ballet of Canada, whose founder and former director Celia Franca was responsible for the splendid Joffrey staging. The ballet was mounted for Ballet Theatre in 1956 and first entered the Joffrey repertory in 1975; the present revival is new this season.

Kay Ambrose's extremely charming decor and costume designs have been lovingly re-created by Edward Burbridge (decor) and Ray Diffen (costumes). Like Offenbach's saucy waltzes, polkas and galops, the physical side of the production is all of a piece with Tudor's conception.

As the curtain rises we see a Parisian cafe' (a window sports the legend "Le Bar Can-Can") in midnight blues which reverberate in the shades of the costumes. A shy bohemian painter (Philip Jerry) works at an easel; his model (Tina LeBlanc), in white and pink, is the naive young daughter of Mme. La Patronne (Trinette Singleton), who's tending the bar. Gradually the place fills with its nightly complement of revelers--stock characters swiftly and expertly sketched by Tudor's choreography.

There's a blushing Debutante (Lauren Rouse) and her friends; a swaggering noble (His Imperial Excellency, portrayed by Jerel Hilding); an amorously fluttering operetta star (Denise Jackson); a snappily uniformed Young Officer (Luis Perez); the floridly grandiose Queen of the Carriage Trade (Patricia Miller); and assorted gents, ladies and waiters. Thereafter it's wave after wave of carousal and flirtation, with Tudor keeping the whole boisterous flow in unceasingly sharp focus.

Sooner or later, each of the principals has a go at another's partner. The dancing swirls to an intoxicated boil; there's a near duel; a sexy, frenzied can-can; and universal exhaustion. In the end, the stage empties to its tranquil opening state, the painter, his model and her wearied mother left alone with the evening's memories. There's a whole tradition of this sort of ballet--Massine's "Gaite' Parisienne" and Lichine's "Graduation Ball" are other examples. It may well be that "Offenbach in the Underworld" is the most skillful and endearing of the lot.

The Washington premiere of Laura Dean's "Fire," with decor by architect Michael Graves and a score by Dean herself, was a serious disappointment despite the dancers' energy and conviction--serious because Dean has demonstrated manifold gifts in previous works (including her earlier commission for the Joffrey troupe, "Night") but really seems to go off the rails on this one.

Of Dean's earlier spare, taut minimalism there are only vestigial traces in "Fire"--some spinning, ritualistic group formations, musical ostinatos. Instead, she's gone overboard on her recent trend toward balleticism; the result is an incongrous me'lange of classical steps, pseudo-orientalisms, and Dean's own idiosyncratic patternings. Graves' pastelly, neo-surrealist landscape and vaguely antique costumes only serve to accent the artifice--nothing matches anything else. There's one section, just before the anticlimactic final duet, a sort of march that feeds back into itself as it grimly advances, where one feels Dean in full control of her materials--elsewhere, it's more like patchy groping in inhospitable terrain.

The program began with a briskly virtuosic performance of Gerald Arpino's shallow, typically frenetic showpiece, "Suite Saint-Saens."