Stuart Skelton and Nina Stemme in the title roles of Wagner's “Tristan und Isolde.” (Ken Howard / Metropolitan Opera)

Opening night at the Metropolitan Opera is a gala, with ball gowns and celebrities studding the red carpet along the lobby’s arcing staircases. It takes commendable chutzpah to use this event as a platform for a five-hour Wagner opera — particularly in a dark and gritty production. On Monday, the Met opened its season with “Tristan und Isolde,” loaded with major international talent, on the same night as the first presidential debate. Those who decided to attend the opera instead definitely won.

The Met stacked the deck with its casting. Nina Stemme, who sang Isolde (and sang Brünnhilde in the last of Washington’s three “Ring” cycles this spring), is arguably today’s leading Heldensoprano: a Wagnerian for the 21st century, on a human scale rather than larger-than-life, her voice indefatigably pouring out rivers of sound but always closely connected to the words she is singing, sometimes fragile and tiny and vulnerable on the huge dark stage. There is, perhaps, a slight sense of calculation, but you could argue that you need calculation to sing a monster role like this successfully. The Liebestod, the opera’s concluding scene, was as painful and private and beautiful as this transcendent aria about transcendence needs to be, after the travails of an emotionally wrenching night. 

Sir Simon Rattle was a luxurious presence in the pit, and an interesting match for Stemme: He, like her, exuded cool mastery and a touch of calculation. He led the orchestra with the kind of incisive clarity that’s a hallmark of the Berlin Philharmonic, where he has been principal conductor since 2002 (a tenure that will end in 2018). But his performance also had a calm remove, letting the orchestra flow rather than driving it — with the exception of the Act II love duet, which took on the headlong, pulsing, unbearable, evocative urgency it requires. Overall, the effect was that of laying a clear pane of glass over Wagner’s score, bringing it into sharp focus while at the same time keeping it at a distance. 

The tenor Stuart Skelton was less sharply defined as Tristan. He had moments of real vocal beauty, with a melting quality to the singing that’s not found often enough in this repertoire, but he was consistently overshadowed in duets by Stemme’s penetrating voice and razor-sharp portrayal. In Act III, however, he gamely tackled one of the hardest sings in opera and brought out the anguish and inner torture that was a particular feature of this character in Mariusz Trelinski’s production. 

“Tristan” is a profound and somber opera, and Trelinski brought out its darker sides in a production that sometimes got in the way of the story, with interspersed videos and occasional interruptions of the action at key moments, but that nonetheless had a consistent vision that came across: fundamentally isolated characters drifting in and out of their own inner consciousness. In Act I, set designer Boris Kudlicka created a multilevel cutaway of the warship in which Isolde’s stateroom is claustrophobically sandwiched between the bridge and the below-decks storeroom where she eventually meets Tristan. Connecting the levels, at one side, is a stairway where crew members roughed up Brangaene (Ekaterina Gubanova, with a silvery soprano quality to her mezzo voice) as she bears messages between them. Act II started high on the ship’s bridge and continued in another storeroom, love playing out in an unforgiving industrial wasteland surrounded by canisters and rotating fans. In this muddy space King Marke, his white uniform one of the few touches of light in the darkness, was a futile defender of clarity and rightness — particularly as sung by René Pape, who remains unequaled and magnificent in this important but usually thankless role. Evgeny Nikitin was a grizzled presence but vocally sound as the faithful Kurwenal, here given the futile task of trying to coax Tristan back to life. The production will be controversial, but the cast will not be, and the Met deserves kudos for choosing art over glitter on a gala evening.

Tristan und Isolde continues through Oct. 27 at the Metropolitan Opera in New York. The performance Oct. 8 will be broadcast live in HD to movie theaters around the world.