"Il Trittico" (The Triptych), Puccini's last complete opera, poses such challenges that it resists production, yet all the while enticing with spectacular gems.

The opera consists of three one-act operas, "Il Tabarro" (The Cloak), "Suor Angelica" (Sister Angelica) and "Gianni Schicchi," linked by themes of love and death and progressions of moods, but otherwise quite distinct. Each requires a different set, different character and vocal types, and different styles of staging. In practical terms, it's more like trying to produce three operas in one night.

Opera being opera, even one-act short stories are not short, which makes for a longish evening. Small wonder the complete work is rarely performed.

Fortunately, Hawaii Opera Theatre has taken on "Il Trittico's" challenges, and with such skill that at Friday night's opening, only the work's abundant strengths were noticeable.

First and foremost was, of course, the music.

"Il Trittico" is sumptuous and compelling, from overall structure to down to the last detail. Heard as a unit, the acts function as "movements" — the first serious and passionate; the second, slow and lyrical; and the third a light, witty presto —creating a single, emotionally satisfying experience.

Puccini's complex tapestry of shifting aural ambience is spellbinding: gently rocking waves segueing into backbreaking work, passions roiling beneath words, juxtapositions of lighthearted and murderous, of hope and despair, at times in the same passage.

In fact, on Friday, and particularly in "Il Tabarro," Conductor Ivan Troezs and the Honolulu Symphony conjured a musical world so entrancing, it very nearly eclipsed the visual aspects.

Similarly, the singers, and particularly the leads, proved riveting in their multiple roles. Words fail with baritone Jake Gardner (Michele and Gianni Schicchi), who did not play his roles so much as became them — wonderful voice, wonderful actor.

Central in two of the three acts, Barbara Divis (Giorgetta, Sister Angelica and Lauretta) carried a heavy load with grace on Friday, her large, warm soprano substantiating each role. Although Divis' upper reaches sounded constrained, her show-stopper, "O mio babbino caro!" was a treat and matched her voice perfectly.

Kip Wilborn, who has a medium-sized tenor with very good tone, made an excellent Rinuccio, full of light humor. As Luigi, he seemed to lack the darker streak Puccini painted in, but served as a good foil for Michele and Giorgetta.

The secondary leads rounded out a strong cast: Katherine Ciesinski sang a thoroughly despicable Princess (brava!), and Sondra Kelly created a great bag lady (Frugola). Notable up-and-coming Mae Z. Orvis Opera Studio voices included Jeremy Blossey, Jacqueline Quirk, Rosanna Perch, Amy Healey and James Price.

A second major strength on Friday was the design team. Peter Dean Beck (sets and lighting) and Richard Stead (wigs and makeup), with costumes by Helen E. Rodgers, tackled what is one of the triptych's greatest challenges — three completely different settings in one night: a barge docked at sunset in 19th-century Paris for "Il Tabarro"; the courtyard, gardens and parlor of a 17th-century Italian convent for "Suor Angelica"; and the bedchamber of a wealthy man in Renaissance Florence for "Gianni Schicchi."

Their designs focused attention on the universals of human nature by using the same basic elements in all three operas: silhouetted skylines as background, with exposed scaffolding to suggest physical structures. Life's details, in various furnishings, props, wigs and costumes, conveyed inconsequential differences in time and place.

However universal the themes, it was HOT's attention to detail that made the production so delightful: light reflecting onto the barge from an unseen river; a slowly fading sunset mirroring the waning of relationships and life; the descent into darkness from a draught of poison; cloistered walls becoming prison bars. ... Such details were visible everywhere for those who cared to notice and created subconscious convictions even in those who did not.

Thirdly, and most importantly, Director Henry G. Akina's vivid staging ensured the production's success. Throughout, the pacing followed every twist and turn in the score, and although not even Akina's cleverness could entirely offset the lag built into "Suor Angelica," it did provide lively, engaging drama.

Akina used his forces judiciously yet fully, finding ways to move people on and off stage in a way that filled out the story line and that flowed well. He used the chorus with particular skill, which helped them create several memorable passages.

Akina outdid himself in "Gianni Schicchi," where the staging finally upstaged the music, even though, as in Mozart, it was the music that created the action. Delightful examples abounded.

But, alas, here the curtain must be drawn, lest divulging details detract from experiencing it.