In Mozart's delightfully farcical opera Così fan tutte, everyone is culpable. The title—roughly, "They're all like that"—refers to the fickleness of Woman, the hypothetical Fiordiligi and Dorabella in particular (sung by Leah Sapko and Kristina Reagle in Thursday's performance) but their fiancés Ferrando and Guglielmo (David Vogel and Jonathan Nussman) likewise prove themselves to be utter cads in the course of their very complicated attempt to prove the sisters' fidelity.

The Boston Conservatory production, set in a ice-cream-colored Neapolitan health spa, is inventively staged to implicate not just the major players—the unfaithful lovers, their scheming maid, and their charmingly skeezy friend Don Alfonso (William Roberts), who's Dungeon Mastering the whole thing—but to embroil everyone on stage. Directed by Sally Stunkel (the Conservatory's Director of Opera Studies), the cast was constantly in motion. Members of the chorus were given a multitude of tasks, some menial, some decadent, gardening and housekeeping and drinking and flirting silently until called upon to sing in support of Don Alfonso's elaborate ruse. Though Vogel's voice was sometimes overwhelmed by the orchestra, he and Nussman were a terrific comic team as they played at being exotic seducers. One sang unbecoming pickup lines while the other gesticulated: a mustachioed, pseudo-Albanian Jay and Silent Bob.

Sapko and Riegle also engaged in some wonderfully physical acting, fluttering, swooning, making war with roses, and sharing gorgeous duets and a wonderful rapport throughout. Despina (Ariana Valdes), the soubrette who traditionally steals the show, stole the show. Among all the dramatis personae, the disgruntled maid's motivations are the least complicated—motivation, singular: cash money—and somehow the most sympathetic. Stunkel employs her in many of this staging's clever embellishments: where the libretto calls for her to whip up some hot chocolate, Stunkel has equipped Despina with a bottle of rum to spike the proceedings.

These performances had to compete with some unfortunate distractions: the Boston Conservatory Theater projects the translated English supertitles a little too high above the stage for comfort and, by the time we'd reached the intermission, the auditorium had became uncomfortably warm, provoking the audience to fan itself with program booklets. (One gaggle of women up and left, vacating seats that were promptly Fenway-Parked by more faithful patrons.)

The Boston Conservatory's production of Così fan tutte will have one last performance at 2 p.m. this afternoon. Tickets range from $5 to $20.

Pictured: Allison Provaire, Monica Thakkar, and Desiree Maira, in Friday's and Sunday's cast, photographed by Michael Fein.

Bostonist thanks our steadfast friend Fancy McCulture-Pants for her assistance with this review.