Purity, while an esteemed virtue, can nonetheless pose challenges to the impure majority, whether in the world as a whole or in that tiny domain inhabited my opera lovers.

Few in that world would deny that Bellini’s scores boast musical episodes as beautiful as any other music by any other operatic composer. However, only one of the composer’s works has truly attained standard repertoire status: Norma, with its incomparable score written to a tight, evocative libretto — which is a rarity for Bellini. His other operas tend to spin gold out of cornpone (La Sonnambula) or outdated romantic hogswoggle (Il Pirata). In the case of I Puritani, Bellini selected one Carlo Pepoli to craft the libretto, although the poet had no libretto experience.

The resulting work, set in the Cromwellian revolt against Catholic Charles I, has a passable first act that sets up a love triangle, the first side of which is represented by Sir Riccardo Forth, who suffers from an unrequited passion for Elvira. She is in love with Lord Arturo Talbo — a love that is very much requited. But when brave and honorable Arturo flees on his wedding day in order to save the widow of Charles I from his Puritan compatriots, without telling anyone, Elvira goes mad. Act two consists of little more than Elvira losing her mind, and then act three restores her sanity with Arturo’s return (with explanation). The triangle has become a footnote by then.

For a production new in 2009, director Pier’Alli apparently trusts the music’s ability to override the weak libretto. Different viewers may find his trust repaid or misplaced, to varying degrees. The stage is all but bare, with tall walls in back, the openings between which reveal a blue background. In act one those openings contain gigantic swords, standing as if thrust into the ground. Since militarism is just a context for the true story of frustrated and then recovered love, this comes across as just a design affect. The only true creativity comes in the director’s costumes, which are traditional and handsomely detailed. Beyond that, evidence of the director’s hand can’t be easily found. The large chorus tends to move into place and stick there. The lead singers march to the center of the stage, find their mark, and sing. Perhaps the director deserves some credit for Nino Machiadze’s subtlety. As Elvira, the soprano doesn’t do any eye-rolling or stage-lolling. She lets her unalloyed love for Arturo shine out of her eyes in act one, and then she lets the life drain out of her visage as she loses her metal equilibrium in the last two acts. The soprano’s voice has a tartness that also helps undercut the role’s tendency to one-dimensionality. At this relatively early stage in her burgeoning career, a performance such as this shows that Ms. Machiadze will focus on her craft rather than on the allure of histrionics.

And that’s a quality that the Arturo, Juan-Diego Florez, has demonstrated since his career’s inception. Although some may prefer a juicier voice in this role, Florez has the secure high notes and agility that the music requires, and he looks quite good. Unfortunately, beyond these two talented leads, the cast declines in appeal. The opening scene goes to a minor character sung by one Gianluca Floris, who has a most unappealing character tenor. Ildebrando D’Arcangelo brings a stolid bass sound to the stolid role of Elvira’s uncle, and Gabriele Viviani is less than vivid as the ostensible alternate love interest, Sir Riccardo.

When Machiadze and Florez are on stage, whether separately or together, this I Puritani works very well, allowing for the inherent weakness of the story and its characterization. The true worth of the opera is in its music, and they both represent that very well. But given the paucity of Pier’Alli’s design concept and stage direction, and the less than glamorous supporting cast, this can’t be called a model I Puritani. Nonetheless, there’s not a lot of competition when it comes to this title. The picture and audio quality can’t be faulted, and the Bologna forces play very well for young conductor Michele Mariotti. If a static and handsome production can be accepted, and if one’s focus is primarily on the two leads in this opera, the Bologna I Puritani fits the bill.

Chris Mullins