If you're curious about the operas of Vincenzo Bellini, there are enough bright moments in the generally gray Washington Opera production of "I Puritani" to give some sense of its peculiar, bel canto mix of absurdity and wiltingly beautiful music.

If you already know and love the operas of Bellini, then let the buyer beware when it comes to the new staging that opened at the Kennedy Center's Eisenhower Theater on Wednesday evening. And if you own the great Callas recording of 1953, and the freakishly inadequate Mexico City recording of 1952, and the excerpts she sang . . . well, you probably weren't planning to attend anyway. In fact, you probably haven't left the house since Joan Sutherland retired. And to be frank, I doubt you're even reading this because newspapers are generally read by people who live in the real world.

Bel canto--literally "beautiful singing"--describes the great naive era of Italian opera when pure vocal line transcended all, including narrative coherence. Bellini, who lived a tragically brief life (1801-1835), was the form's purest practitioner, giving the world arias, duets and ensembles that remain the supreme touchstone of fine Italian singing. But he was a purist when it came to absurdity as well; his plots boggle the mind, and "Puritani" may be his best bumper crop of unlikely events and poetic flapdoodle. Pound your Roundhead against the impenetrable logic of this tale of English Puritans and Royalists, and it still never quite hangs together.

Not that this matters. Not a bit. Bellini lovers are perfectly willing to sit through an opera in which Oliver Cromwell is the good guy, the Puritans sing in church, and the lead soprano goes mad not just once but twice--so long as the deal is sealed with the promise of spectacular, spine-tingling singing. Even sensible Queen Victoria, who could have found the English Civil War plot offensive, given her distant family connections, named it her favorite opera.

But it is a hard bargain that the Washington Opera offers. On Wednesday, some very fine young singers took on the major characters, but they were not all well chosen for their roles, and they did not blend well when singing together. This opera lives or dies on the strength of its prima donna, the soprano who sings Elvira. Lynette Tapia has a small, refined and well-trained voice, but it is not dark or heavy enough to sing this role. Yes, Elvira is a flighty 16-year-old with a tenuous grasp on reality, but she is not merely a soubrette; the singer needs to darken the voice at critical moments, to lounge heavily in the anguish of arias such as "Qui la voce." Tapia captures well Elvira's joyful (and happily delusional) moments; she has a bright, fast voice that only occasionally lagged behind the beat. But she's not yet an Elvira.

The Washington Opera has made much of Tapia's real-life marriage to the principal tenor, John Osborn (devoting an article on the subject in its magazine). But what God has joined together is not necessarily what Bellini would join together; they are an attractive young couple onstage, but their voices don't pair well in this opera. Osborn, who sings Arturo, the Royalist hero who chooses duty over love but gets the girl in the end anyway, has markedly different tone qualities in his voice. The mid-range is warm and comfortable, but when he opts for the impressive top notes, veins bulge and the sound gets a bit bloodshot. They are not light top notes, and they overwhelm Tapia's more delicate soprano.

Bass Daniel Sumegi (seen last season as the Reverend Hale in "The Crucible") is the best-cast singer in the production. As Giorgio, he covers notes with fullness of tone, and has the substantial breath support to sing a true, seamless Bellini line. His stage presence as the loving father figure, an alpha male with beta sensibilities, was also the most dignified and convincing of the evening. Baritone Jorge Lagunes, as Riccardo, sang a very rousing "Suoni la tromba" with Sumegi--they at least blended nicely--but he took a long time to warm up. That, plus a scrappy overture (conducted by Christopher Larkin) and some tentative choral singing made the opening of the opera rough going.

Charles Roubaud's staging is nondescript, making no apologies for, nor any efforts to hide, the dramatic implausibility of the libretto. The blocking of the chorus was awkward and campy, hampered by Isabelle Partiot's stage design: a series of guillotine-like drops that reveal a two-dimensional design of intersecting ramps, running at angles offstage. This complicated the natural flow of things. The arrival of six trees (just six) to signal the Act 3 forest scene might work at the end of a stylized "Macbeth," but seemed a bit barren for England.

The economizing in this production is palpable. The staging is a co-production with several other opera companies in France and Belgium, but it didn't sparkle in the Eisenhower Theater. "I Puritani" is new to the Washington Opera, and while the company is still growing and learning, it might make more sense to present concert versions of operas that are this tough to bring off. That's how the Washington Concert Opera presented Bellini's "I Capuleti ed i Montecchi" last fall, and musically the results were much more satisfactory. (Two separate casts will sing "I Puritani." The second cast debuts this evening.)