Joseph Haydn's opera "Il Mondo della Luna" ("The World of the Moon") is a bit of comic fluff, not the archaic science fiction opus its title seems to promise. But it is a delightful bit of fluff, still fresh and funny after 225 years, with beautifully crafted music and many opportunities for well-sung comedy and imaginative stage design. Except for design, its potentials were brilliantly realized Sunday in a concert performance by Opera Lafayette at the University of Maryland's Clarice Smith Performing Center.

Haydn is recognized as a towering figure in the history of symphonies and string quartets, but his ability as an opera composer (not far below Mozart, but a bit less complex) is less well-known. More performances such as this one would help.

The libretto, by Carlo Goldoni, had been set to music several times before Haydn took it up, with a revised third act, to open a new opera house at Esterhaza Palace.

The plot has a theme familiar in comic opera: essentially, sorting out young couples (three of them in this story) and making sure the pairings are right for marriage. The obstacle is Buonafede (Francois Loup), who is tyrannically protective of two daughters, Clarice (Amanda Balestrieri) and Flaminia (Kirsten Blase), and hopes to marry his maid, Lisetta (Heather Johnson). Three young men want to marry them: the astrologer Ecclitico (Robert Baker), his friend Ernesto (David Newman) and Buonafede's servant Cecco (Marc Molomot). The lovers get the father's permission to marry by drugging him and convincing him that he has been transported to the moon, a delightful place whose emperor (Cecco in disguise) wants to marry Lisetta and insists on marriage for the two other couples.

Besides the marriage motif, a traditional comic plot element is the figure of the imperious but foolish old man, a figure that Loup has portrayed in many operas and handled brilliantly in this one. His voice, like all the others, was excellent, and the music seemed tailored for him. Baker was an impressive, almost sinister, foil for Loup's befuddled antics. All three women sang extremely well, Balestrieri and Johnson with strong stage presence and comic verve, Blase with spectacular high notes and coloratura agility. Molmot and Newman were vocally and theatrically just right. Ryan Brown conducted the singers and the excellent period-instrument orchestra with a finely tuned sense of the proper style.

Leon Major's ingenious stage direction had no scenery but did wonders with costumes, props and the singers' stage movements, as well as thematic images projected on a large screen that also handled unusually readable surtitles.