Life imitates art. Recent news out of Britain is that a married couple discovered that they were actually twins separated at birth, the central plot device of Richard Wagner’s “Die Walküre.” The press has kept the secret of the couple’s identity, but some enterprising reporter might want to peruse the London directory for a listing under Wälse. On Monday evening, the Metropolitan Opera House presented two significant new cast members in the work.

Deborah Voigt joined the troupe as Sieglinde, a role that she has sung here many times before. Ms. Voigt was in fine voice, able to handle everything thrown at her with grace and aplomb. She never faltered and was especially impressive in louder, more anguished passages. Also pleasing was the effort made by the company to portray her and the Siegmund, Clifton Forbis, as actual twins, right down to hairstyles and makeup.

Something elemental was missing from her performance, however. There was little sense of the character itself. Ms. Voigt never appeared youthful or anticipatory. A listener not familiar with the story would have been surprised to learn that she was undergoing the sweet pangs of love. When she sang “Du bist der Lenz” (“You are the Spring”), there was no hint of the ecstatic. One of the two most throbbing love duets in the entire literature — the other being Hector Berlioz’s “nuit d’ivresse” from Les Troyens, which the composer penned after being granted a sneak peek at the working score of Die Walkuere — cried out for much more electricity.

Some of its phlegmatic treatment may have been engendered from the pit, where Lorin Maazel led a briskly paced but ultimately declarative rendition. What was missing this night was the frisson of a James Levine performance. By contrast, completely in character was the vibrant Fricka of Michelle DeYoung, also having her first turn in this current cast. This is the pivotal role of the opera, in terms of both structure and definition of its moral compass.

Wagner lets us know right from the first notes of the piece that the story revolves around the impotency of Wotan, the opening storm consisting of broken shards of the phallic spear motif. Ms. DeYoung has only one scene to make her presence known and she makes the most of it. Powerful in both physical presence and vocal strength, she ran a marathon of emotions — from anger to sadness to flirtatiousness to triumph — in a few short minutes. The audience could almost see the Wotan of James Morris shrink before their eyes.

The remainder of the company was held over from the premiere. Mr. Morris is magnificent as the sinking leader, at this point in his career the Wotan of an entire generation, profoundly a little bit weaker in each progressive scene. Mr. Forbis was a superb heldentenor hero, resoundingly ringing out those loud “Wälse notes” with purity and courage. Mikhail Petrenko was an oddly non-threatening Hunding, while Lisa Gasteen was so weak a Brünnhilde that her initial battle cries elicited actual laughter from the gallery.

Two seasons ago in Paris, I had the opportunity to view the Robert LePage production of “The Damnation of Faust” by Berlioz, which will be coming to the Met next year. It was highly inventive, and now Mr. LePage has been granted the assignment to produce a new complete “Ring” cycle to premiere in 2010 here in New York. But when that day comes, it will be a sad one, for the visual effects of this current “Ring,” conceived by Otto Schenk, are as timeless and as powerful as the story of “Die Walküre” itself.