Sometime in the fall of 1852, the composer Giuseppe Verdi decided that his next opera would be based on Alexandre Dumas’ play The Lady of the Camellias. The play, which had been a hit in Paris earlier that year, was a semi-autobiographical story about a high-end prostitute, her love for a young bourgeois gentleman and her eventual death from tuberculosis.

With its sympathetic but unsentimental depiction of a “kept” woman, its harsh critique of social hypocrisy and its contemporary setting, the play deployed much edgier source material than opera was used to. The censors insisted that Verdi’s adaptation, La Traviata (“The Wayward Woman”), be moved back to the less threatening period of “circa 1700,” infuriating the composer, who clearly relished the story’s immediacy. a few months earlier, Verdi had written to a friend that the play was “un soggetto dell’epoca”—”a modern subject,” “a subject for our own time.”

That famous quote has remained something of a puzzle over the past 150 years, during which time La Traviata, with its gorgeous music and riveting plot, has become one of the world’s most beloved and popular operas. Did Verdi mean that the story was timeless? Did he want us, in 2011, to set the opera in the 1700s, or the 1850s, or 21st-century new York? Whose “epoca”?

These aren’t academic questions. Our understanding of what “un soggetto dell’epoca” means is key to thinking about how, so long after their composition, we are supposed to stage the operas of Verdi and his generation, as well as why we go to the opera in the first place, what is essential to the art form.

It can be hard to see these days what the censors were so upset about. Popularity has tended to dull La Traviata’s once vivid impact. It has turned into a costume drama, a velvet-lined Masterpiece Theatre miniseries. For over 20 years, the opera has been particularly ill-served at the Metropolitan Opera. In 1989, the Met opened a Franco Zeffirelli production that the critic Daniel Mendelsohn called “sumptuously unimaginative.” The sets were enormous and ornate; it was hard to locate the characters, let alone follow their drama or feel its relevance. It was replaced in 1998 by an even more sumptuous, even less imaginative production by, once again, Franco Zeffirelli.

On new Year’s Eve, though, the Met introduced a stunningly different interpretation of the opera, directed by Willy Decker. The costumes are modern (21st-century modern, that is); the chorus, men and women alike, is dressed in identical dark suits; the set—eerie, disorienting and strangely sensual—is little more than a curved, neutral-colored back wall; an oversize clock is a perpetual reminder of the death of Violetta, the wayward woman of the title; the style teeters, as does the opera itself, between realism and stylization.

As the elegiac prelude begins, doors swing open, and Violetta stumbles out in a red cocktail dress, preparing for a party but unable to ignore the wasting symptoms of the disease that is killing her. an older man sitting on a bench along the wall turns out to be Doctor Grenvil, a minor character that mr. Decker has transformed into an omnipresent specter of death. but this seeming directorial liberty is in fact suggested by the libretto, which indicates that the opera opens with Violetta sitting “with the Doctor and other friends”; the composer clearly wanted us to associate them from the very beginning.

The production is full of such moments, surprises that nevertheless are drawn from, and illuminate, what Verdi wrote. At the end of Act II, Violetta has been forced to leave her lover, Alfredo, who confronts her at a party. In most productions, he insultingly throws his gambling winnings at her feet, but mr. Decker has him stuff the money angrily into her cleavage and up her skirt; it’s extreme, but the anger of the music, and of the chorus that follows, finally makes sense. At the very end of the opera, when Alfredo and his father have joined the dying Violetta, she gathers them to her side and practically spits at the doctor words usually delivered meekly: “You see, Grenvil? I die in the arms of those dearest to me!” It sums up in a moment the nobility and futility, the breathtaking pathos, of Violetta’s defiance of death. Consistent with the text, but thrillingly unexpected: this is a truly theatrical vision of opera.

Marina Poplavskaya’s Violetta is, in keeping with mr. Decker’s fatalistic conception, resolute but helpless, moving listlessly in circles. She’s brittle, not soft; fragile rather than vulnerable. You’re wrenched by this Violetta, but you don’t weep for her. It’s not exactly her acting that makes the production work so much as her stage presence. From moment to moment, there is a lack of specificity, a blankness that may well have been her interpretation of mr. Decker’s instructions, but she is magnetic, at her most fascinating when standing quietly, watching other singers. mr. Decker has obviously choreographed the production down to the smallest gesture, yet Ms. Poplavskaya makes its inexorable progress seem natural, even spontaneous. The end of the first act, which requires repeated high Cs and coloratura flexibility, is difficult for her, but her large, dark voice is haunting throughout. In the second-act duet with Alfredo’s father, she seems physically transformed by loss. Standing at the edge of the stage for an ethereal “Dite alla giovine,” far closer than you ever get to singers at the Met, she is suddenly emaciated, empty.

The genial Matthew Polenzani, as Alfredo, was in his element in the happy moments. In the more ardent, tortured sequences—his scene with his father, his outburst against Violetta—he seems less comfortable and clear; lots of rehearsal-room ideas haven’t yet gelled. As his father, Andrzej Dobber was suave and perhaps even too sympathetic: In a production as stark, with a Violetta as isolated, as this one, such warmth actually distorts the drama.

Mr. Decker’s stylizations and broad, occasionally overwrought symbols, though intelligent and grounded in the music and text, sometimes distance us from the opera as much as mr. Zeffirelli’s lavishness did. but at least mr. Decker’s work feels new. If a contemporary theatergoer went to see Hamlet and found this set, he wouldn’t bat an eye, but at the Met, for Traviata, it’s startling, and that, in itself, is something. It’s been a long time since a Met production of the opera (or most any repertory staple, for that matter) was really surprising, capable of changing your perception of the work and its possibilities, reminding you of the elements of its drama—the double binds faced by women; the uneasy, codependent relationships between classes; our fascination with spectacles of suffering-that make it, as much as ever, un soggetto dell’epoca.