I have attended many of the productions staged at Merrill Auditorium by PORTopera, and this year’s “Madama Butterfly” stands out as one of the finest.

Wednesday night’s performance appeared to be entirely sold out, but good balcony seats are still available for today and should go fast.

One expects world-class singing from PORTopera, but artistic director Dona Vaughn has outdone herself this year in pulling everything together — a gorgeous set, authentic costumes, lively stage direction and, most especially, near-perfect casting. The orchestra, under Stephen Lord, would grace the pit of the Metropolitan.

If I had one word to describe this production, it would be “intensity.” The center of this feeling is Vaughn’s concept of Cio-Cio San. A play called “Steel Magnolias” comes to mind.

Madam Butterfly is nobility personified, adamant in her ideas of love, loyalty and a better land beyond the sea. But she is never a victim, even in her suicide with an ancestral sword.

Soprano Inna Los as Cio-Cio San realized this concept to perfection. Her voice can be light and flirtatious in the upper registers and deadly serious in those closer to the spoken word, but always enchanting. She is also a fine actress, with telling small gestures, such as renouncing the cross and bowing to the old gods before her death.

Her strength of character is exemplified in the scene in which she waits all night for Lt. Pinkerton to arrive, standing rigid in one pose while those around her fall asleep. The vision lasts a long time, supported only by Puccini’s music, but is central to her character.

Tenor Adam Diegel, as Pinkerton, portrayed a man gentler, more complex and conflicted than usual in this role. He is the real victim, flawed, conventional and falling short of Cio-Cio San’s ideal. The voices of Diegel and Los were perfectly matched, making the duet “Viene la sera” a delight to hear again, in a new context.

Mezzo-soprano Heather Johnson was also fine as Suzuki, Cio-Cio San’s strong support, even though she realizes that her ideals will never be realized. The scene in which she grabs the sleazy marriage broker, Goro (sung by tenor John McVeigh), by the ear and throws him down, managed to be both funny and telling.

My favorite in all productions of “Butterfly” is the Graham Green-like character, the American consul Sharpless, secretly as much in love with Cio-Cio San as her foolish suitor Prince Yamadori. He serves the function of a Greek chorus, predicting and trying in vain to avert the tragedy. Baritone Edward Parks was outstanding in this role.

All of the other characters were equally well cast, from Claire Caton, as Cio-Cio San’s child Sorrow, to mezzo-soprano Eliza Bonet as Kate Pinkerton, revealing a (somewhat) warm heart under the most frivolous exterior.

A tragic evening ended in catharsis, with smiles, bravos and lots of bows by the excellent company.

Christopher Hyde’s Classical Beat column appears in the Maine Sunday Telegram. He can be reached at classbeat@nescape.net.