Love, mercy, and harmony triumphed over a corrupt, lustful tyrant on Sunday afternoon at the Isabella Stewart Gardner Museum, where the early music ensemble ACRONYM resuscitated Alessandro (father of Domenico) Scarlatti’s rarely performed and yet-to-be-fully-recorded La caduta de’ Decemviri (The Fall of the Decemvirs) in the group’s instrumentally excellent but vocally uneven Boston debut.

The opera, Scarlatti’s first collaboration with Silvio Stampiglia, who would become one of his favored librettists, dates to 1697, at the peak of Scarlatti’s operatic success during his first tenure in Napoli. The plot offers a happy-ending alternative to an episode in Livy’s generously juiced-up chronicle of the 5^th-century BCE Decemvirate, when a 10-man commission ruled the Roman Republic.

According to Livy, Appius Claudius rigged an election to establish authoritarian rule under himself and nine cronies. When a beautiful plebian girl caught his fancy but rebuffed his advances, he had a henchman claim she was the latter’s slave, then ruled in his proxy claimant’s favor against the contestation of the girl’s father, who stabbed her to death to preserve her honor and rallied a rebellion in revenge.

Scarlatti and Stampiglia turned this into a convoluted but often sweetly humorous romance―more in the spirit of A Midsummer Night’s Dream than The Rape of Lucretia. Appio Claudio’s former flame Valeria is the Helena, desperately devoted to but shunned by her beloved as he pursues resistant Virginia, while his sister Claudia pines for Virginia’s warrior father Lucio, who secretly reciprocates but dares not voice his plebian passion for a patrician. In the end, Virginia recovers from her father’s stabbing to reunite with her betrothed, Icilio. Her shrewd nurse Servilia captures Appio’s flunkey Flacco as he attempts to flee in drag. Lucio and Claudia declare their love for each other. Valeria not only brokers a peaceful transfer of power from Appio’s gang of ten to Lucio and Icilio, but also wins both life for and love from repentant Appio. Four couples pair up for the happily ever after. Sic semper tyrannis? If only!

In a conductor-less concert performance not so much semi-staged as semi-acted, with gesticulation and interaction among singers in suits and cocktail dresses, the cast of eight tackled the unfamiliar score to varying effect. Calderwood Hall’s up-and-around-the-chimney configuration poses a puzzle to any performer,* but musical quality differed greatly between singers even within tripping distance on the floor level. A little directorial guidance in both vocal and physical dramatics could have evened and elevated the level of performance significantly.

In the lead role of Appio Claudio, countertenor Daniel Moody ruled the room, laying waste to any acoustic challenges that may have hampered some of his colleagues. Haughty and stentorian in his pronouncements, Moody’s delivery at times seemed more forceful than necessary, but he cut a potently petulant figure of seething appetites and furies, which made his later remorse all the more poignant. “Del caro mio tesoro” (Of my dear treasure) exhibited his interpretive power most fully, as he swung between tremulous longing and grim determination, alternately choking on and gushing out his desire, and all to a text that reads as any generic lover’s list of the beloved’s beauteous body parts.

As long-suffering Valeria, soprano Sarah Shafer deployed a Susanna voice to deliver a Countess Almaviva performance of a Donna Elvira role. Never before sang jealousy so sweetly, with such gentle mournfulness and yearning. Shafer’s impeccable technique, amber-glow bell-tone, and zephyrous line serve her well, even when miscast. At many moments I wished for more edge, rawness, perhaps a brittle, strident vulnerability, and wondered how she might have inhabited the role of Virginia instead. Her ability to hold her own against Moody, however, surpassed her other castmates, so one was grateful not only for her every lovely utterance, but also for the counterbalancing authority with which she confronted Appio at his surrender.

Would that Virginia and Claudia sounded more like Susanna and Countess Almaviva: the one with a warm sparkle of wit and wile, and the other a noble, refined, yet sympathetic peacemaker. Neither Marguerite Krull or Amy van Roekel quite fit the profile.

Countertenor Tim Keeler brought more callow plaintiveness than ardor to the role of Icilio. His wispy choirboy sincerity faltered as grass to Moody’s gale. Likewise, Matthew Anderson’s cantorial tenor ran nimble and bright, with deftly sculpted phrasing in the recitatives, but sounded too dainty to commandeer the battlefield.

The two comedic-relief servants, Servilia and Flacco, were better served by soprano Justine Aronson and bass-baritone Peter Walker. Aronson’s crunchy-as-granola enunciation and saucy-as-Despina inflection presented a lesson in how expressive and compelling recitative can be with real voice acting. The wry and limber bounce to Walker’s suppleness bodes well for great buffo roles to come.

ACRONYM’s ten regular members plus two glorious guest trumpeters played with verve, sensitivity, and cohesiveness. They provided a consistently excellent foundation on which the singers strutted or stumbled. Occasionally, their bursts of brilliance eclipsed all else. They delivered the throbbing, breathless, jagged turmoil of Valeria’s agitation, the loping swagger in Flacco’s declaration of love to Servilia, the twirling ribbons of longing as Claudia contemplates unspeakable love. The strength of their performance argued eloquently for La caduta to rise again.

Far from a proto-feminist, Scarlatti banned his musically talented daughters from public performance even as he lobbied aggressively to advance the careers of his sons. He placed the girls in convents and yanked them out against their will as he pleased. Yet in contrast with operatic repertoire notoriously heavy on female victims, his La caduta presents a refreshing alternate world where the women not only survive but possess the agency to save the day with courage and intelligence. (Virginia’s father still stabs her, but he requests and she grants her permission first—which kind of makes it better?—and she all but bounces right back to life.) Stampiglia’s libretto bubbles with cute little asides and colorful dialogue that a director could choreograph to charming effect. I hope ACRONYM continues to champion and experiment with this piece in different settings and configurations, and that others venture to give it a whirl as well.

Meanwhile, we can look forward to ACRONYM’s return to perform at the Boston Early Music Festival on June 12^th.

* Did anyone hear how the sound projected to the upper levels?

CJ Ru, Yale Ph.D. candidate in history, previously served tours of duty in the administrative offices of San Francisco Opera and Philharmonia Baroque Orchestra & Chorale.