The overture to Carl Maria von Weber’s opera “Der Freischütz” (“The Marksman”) calls up the dusky shadows and sylvan aromas of the German hinterland. It trumpets the glory of an autumn day spent pursuing the hides of harts and the hearts of women—sometimes both at once. It is a piece of extraordinary vigor that makes one understand why John McCain would choose a backwoods Alaskan huntress as his running mate.

Or at least it should do all of this.

But in Opera Boston’s underwhelming new production, playing Oct. 17-21 at Boston’s opulently beautiful Cutler Majestic Theatre, the orchestra fails to transmit the Romantic power of Weber’s music. The musicians, under the baton of Gil Rose, played with confounding restraint, not giving the fortissimo passages of the score their due fortitude. In the final minute of the overture, when the strings should be a band of sprinting hunters, they were instead a flock of pigeons flying languidly overhead. The absurd onstage pantomime that accompanied the music did not help matters, either.

The singers, like the pit, also suffered from want of robustness and intensity. In a season-opener—and with an opera that has not been performed in the Boston area for 25 years—the performers should have been drunk from the first-night excitement. But most of them merely seemed hung-over.

Daniel Snyder, in the leading role of Max, sang with far more urgency than he acted. His movement and expression were often as wooden as the butt of his hunting rifle, which, for a character whose inner psychological turmoil is at the center of the opera, was not welcome. In the opera’s plot, Max is a down-on-his-luck hunter who must win a shooting contest to gain his beloved Agathe’s hand in marriage. Having performed disastrously in a lead-up competition, he turns to a shadowy pact with the Devil to make sure he shoots surely in the all-or-nothing finals. But Mr. Snyder, as well as singer Emily Pulley, who played a fretful and unlikable Agathe, does not act with enough conviction to make anyone really care whether his bullets will land. The bright-voiced and comical soprano Heather Buck, in the archetypal sassy-best-friend-to-the-leading-lady role, fared much better as Ännchen.

The vague and muted acting of most of the ensemble went hand in hand with the production’s unfathomable setting. With “Der Freischütz,” director Sam Helfrich presents a world that, like the acting, is never really sure what it’s supposed to be. He puts Agathe in a traditional German dirndl while Ännchen, in the same scene, wears a form-fitting black blazer and a pair of department store jeans. The chorus of village maidens, bodices laced up and hair braided like so many St. Pauli Girls, drink lager out of disposable frat-party cups. A rustic wooden barrel that looks like it might have been used in the original 1821 production at the Konzerthaus in Berlin, shares space on the stage with a blue plastic trash bin that looks like it might have been purchased at the Home Depot in West Roxbury, Mass. The period and setting are never clear, producing an inscrutable operatic haze that frustrates singers and spectators alike.

The haze finally cleared—though only briefly—in the middle of the third and final act. As Buck was singing a humorous aria called “Einst träumte meiner sel’gen Base” (“My late cousin once dreamed”), an unexpected bang shot through the theatre. The overhead screen projecting the English translations of the sung German had gone blank, and would remain so for the rest of the performance.

The computer glitch proved providential for the opera’s singers. One imagines the backstage panic: “Look, folks, the supertitles are out! The audience will not know what’s happening if you continue to move about like flannel-wearing robots at a sausage shop. You must act! Act, by Gott!” And act they did. Under pressure and in undesirable circumstances, the singers began to gesture and express and emote as they hadn’t done before, and, paradoxically, the story became easier to understand than it had been in the prior acts, when the audience had translations to guide them but no raw emotion to move them.

If only more such happy disasters had come along to save this production from its inconsistent, passionless self.