One of the most exciting operatic developments of the times is the rediscovery of Handel's operas, and there have been few such bright, inventive productions as the one of "Ariodante" that opened here Monday night at the Spoleto Festival USA -- it should influence how other Handel operas are done in this country.

In one of those oddities of history that make no sense, all 36 of Handel's operas that once dominated the London stage pretty much fell out of circulation for more than two centuries. This happened even though anyone who can read a score could look and tell that they are just as full of musical glories as the omnipresent Handel oratorios.

One thing that has been quickly learned in the revival is that these operas are awfully tricky to do -- and that does not refer just to the often-cited absence from our scene of the pyrotechnically brilliant castrati.

Monday night's staging of one of the finest Handel operas -- a marvelous creation by any measure -- was by the Concert Royal and the New York Baroque Dance Company. They did it the hard way -- Handel's way.

Painstaking attention has been given to the exigencies of Baroque style. The seven lead singers -- every single one in a grueling bravura role -- appeared faultlessly schooled in Baroque ornamentation. The orchestra, under Baroque authority James Richman, glowed with the sweet, unforced timbres of period instruments. The lengthy dance interludes that come at the ends of each of the three acts, imaginatively choreographed by stage director Catherine Turocy, impeccably adhered to the discreet proprieties of pre-ballet Baroque dance, with its symmetry, its ornamental hand gestures, its relaxed feet. The splendid sets of Jeffrey Schneider maintained a sense of 18th-century formality, with quite sensitive coloring and lighting.

And, finally, in a touch that only Charleston could provide (in this country, at least), the production unfolded in the cozy confines of a Baroque chamber, the Dock Street Theater (which opened in 1736, the year after "Ariodante" had its premiere at London's Covent Garden).

The Dock Street is the first building used solely for theatrical purposes to be constructed in this country and is believed by some to have been the site of the first performance in America of an opera. With its seating capacity of a little more than 400, it is a jewel of a house.

The net result of all these factors serves to prove the importance of doing Handel just as authentically as we would do "Der Rosenkavalier." As Richman observes in his program notes: "Far from being difficult or stylized, as it has too often been perceived today, baroque opera was immediately communicative to its audiences, who lavished unheard-of rewards and praises on its greatest exponents." In this sense, it echoes the Washington Opera's worthy "Semele" at the Terrace Theater. But this production took Handel important steps further than the Washington Opera is equipped to go.

The people here certainly picked the right Handel opera on which to lavish all this care. "Ariodante" is free of all those gods, goddesses and sorcerers who often dominate opera of its period. It is a psychological drama about believable characters who coexist in a noble's court. It is about love and its vulnerability to sexual jealousy and ambition for power.

The setting is supposedly the court of the King of Scotland (bass Wilbur Pauley) and the issue is who will marry the princess Ginevra (soprano Julianne Baird) and succeed to the throne. The title character is the good guy (sung here by mezzo-soprano Judith Malafronte) and the jealous cur who would spoil it all is Polinesso, Duke of Albany (mezzo Cynthia Miller). In an uncut version "Ariodante" takes about four hours and has a dazzling profusion of arias and duets -- remarkably varied in dramatic character -- before justice can squeak through at the last moment.

The most brilliant of the roles, and it is sensational, is that of Ariodante. On Monday it also was the most brilliantly sung.

Malafronte had arias of dismaying coloratura difficulty and also ones of noble gravity. Occasionally there was a little roughness, but even then she stayed right on top of the notes. Pitch was excellent, as were rhythm, diction and acting.

Baird's Ginevra was more generalized, but she communicated the altering moods of devotion and melancholy. Miller's Polinesso was menacing in all but the vocal sense, though she managed the final aria with a good deal of power. Ginevra's dubious friend, Dalinda, was sung flamingly by Anne Monoyios. The voice was slender but she handled it with sensitivity. As the king, Pauley showed a fine deep bass. The role of Ariodante's brother, Lurcanio, is negligible dramatically but makes enormous vocal demands, ably met by tenor Jeffrey Thomas. Tenor David Lowe was capable as the royal counselor Odoardo.

There were some last-minute cuts to reduce the playing time, eliminating some repeats and parts of the dances. They did not seem to do great harm. And the one production of this opera that Washington has seen within memory, in the early days of the Kennedy Center, was far more drastically cut and made few nods to stylistic authenticity.

Spoleto's "Ariodante" is long sold out, but the production will be repeated in New York in September.