The tables turn at the climax of Tosca.

The famous line that everyone quotes about Tosca is Joseph Kerman's snarky quip that it's "a shabby little shocker."  Well, as Boston Lyric Opera proved last weekend, the Puccini potboiler may be a shocker all right, but it's none too shabby.  Stripped down from a lugubrious, if well-crafted, melodrama by Sardou, the libretto plays like a taut thriller studded with lurid episodes and hairpin turns; this is the rare opera with a palpable sense of suspense (indeed, everything in Quentin Tarantino derives from, and is degraded from, Tosca).  And the score may simply be Puccini's finest.  It not only includes one of his loveliest arias ("Vissi d'arte"), but the second act in particular is (nearly) through-composed with startling sophistication and a superb sense of drama.  The composer relies throughout Tosca on a kind of semi-Wagnerian system of motifs - but unlike Wagner, Puccini doesn't spend time developing them in purely musical terms (while the action stiffens into stasis); instead, he weds his musical motifs almost seamlessly to the drama unfolding onstage.

The parapet in Rome from which Tosca meets her doom.

The plot itself is brazenly heartless; Sardou's constant advice to his protégées was "Torture your women!," and the eponymous Tosca, a vain but good-hearted opera singer thrust into  intrigues she can barely understand, endures one torment after another before a final blow that drives her to a plummeting suicide, from the parapet of the famous Castle Saint'Angelo (at left) - just as the curtain falls, too.  The opera was originally set amidst the battles over Rome between Napoleonic and Neapolitan forces - but the BLO production (borrowed from the Scottish Opera) updates the basic conflicts into fascist Italy: the chief villain, once "Baron" Scarpia, is here a jack-booted chief of secret police, while Tosca's lover, a painter who falls into Scarpia's clutches, is vaguely aligned with the Resistenza.

Not that actual politics matter much in the hothouse atmosphere of Tosca - they're just a means to highly dramatic ends; the final suicide only arrives after two murders, a near-rape, and several scenes of torture (below).  And fortunately, the BLO production doesn't push its "updating" to any obvious Peter-Sellars-esque political morals, either; director David Lefkowich often seemed happy to effectively block his action, then bask in the atmosphere provided by the funereal grandeur of Peter Rice's smashing sets, lit with the burnished rays of a perpetual sunset by Paul Hackenmueller (one glance at these designs, and you knew poor Tosca was doomed).

Even though, of course, she's innocent of everything (except a sudden, murderous impulse which you can hardly blame her for).  This nihilistic theme, of helpless innocence pointlessly punished, was a new one in opera - and a new one on the stage in general - and it still packs a punch, particularly in the moving performance of Jill Gardner in the title role.  Ms. Gardner possesses a rich, but not particularly individual, soprano, and her rendition of the famous "Vissi d'arte" was hampered by blocking (she was half-prone, "imprisoned," if you will, on a bed) that provided a striking stage image but must have given her very little room for breath support.  But Gardner is also a truly wonderful stage actress - one of the best stage actresses I've seen cross a Boston operatic stage - and her Tosca was always both amusingly vain and yet poignantly, vibrantly alive.   And her sudden killing of Scarpia - you could see the mad inspiration dawn on her - chilled just as it should, while the famously macabre, guilt-ridden scene that follows she played to the absolute hilt.  (In one of the production's few surprising flourishes, she threw away with a shudder the crucifix that Tosca usually places in penance on Scarpia's corpse.)

Tosca's lover, Cavaradossi, is brutalized by the minions of Scarpia (far right). Photos by Jeffrey Dunn

Her co-stars were no slouches.  With his hawk-like demeanor, Bradley Garvin looked the perfect Scarpia, and brought a cruel alacrity to the character's various predations - although the voice, though fine, was again not at the high level we've come to expect from such recent BLO productions as Ariadne auf Naxos.  The production boasted one true vocal star in tenor Diego Torre, who was a bit too earthy to be believable as the lover of a grande dame like Tosca, but whose singing was glowingly lyrical, if marred by a phlegmatic scratch (we later learned he took a few days off to battle a bronchial infection), and whose acting rose to a moving, if slightly withdrawn, intensity as he faced imminent death.  There was also a nice comic turn from Steven Smith as an easily flustered priest, and a sweet one from young treble Ryan Turner in the final act as the Jailer's Son.

In that last act the production seemed to stumble a bit - the blocking seemed more tentative, and Ms. Gardner didn't seem as shaken by her ordeal as she might be; moreover the music sometimes flowed over insufficient stage business. Nevertheless, the music was gripping all the same; the sound from the pit - under the baton of Conductor Andrew Bisantz - was always darkly robust (Bisantz did a similarly impressive job, in a very different vein, with last season's Turn of the Screw). It seemed that in this remarkably strong and solid production, any momentary weakness was balanced by a different strength; no wonder the crowd, clearly hungry for this kind of shot of pure operatic adrenaline, gave the cast a sustained standing ovation. A year or two ago, when I began writing that Boston Lyric Opera had turned an artistic corner and would (or should) become the dominant force on the operatic scene, I got several ridiculing emails. Now, after a series of productions as strong as Tosca, that seems to be the conventional wisdom.