Erin Passmore and Melissa Chavez in the In Series production, "Cosi Fan Tutte Goes Hollywood." (Rx Loft Photography)

Well before “pocket opera” became the new cool thing, Carla Hubner and her In Series were bringing small-format opera in translation to informal spaces in D.C. They began 28 years ago, with a version of Mozart’s “Cosi Fan Tutte” and then reprised it several times as “Cosi Fan Tutte Goes Hollywood” with librettist Nick Olcott’s version of what Da Ponte might have come up with if he had lived in the early 20th century. The music remains all Mozart (except for brief forays into “Why-o Did I Ever Leave Ohio” and “Give my regards to Broadway”).

The In Series production has evolved over the years, and the one brought to the Atlas Performing Arts Center on Saturday has matured. Aspiring actress Dorrie, and her sister and agent, Florrie, born and bred in the virginal innocence of mid-American Ohio, exude clueless naivete as they hope to penetrate the Hollywood movie world. They are accompanied by their not-quite-so-guileless boyfriends, aspiring vaudevillians Randy and Elmo. Goaded by movie producer Don Fonso and his sophisticated secretary Tina (all wiggle and attitude), the guys set out to prove that their gals will remain chaste and true, not matter how tempted to do otherwise. That they lose their bet, proving once again that “Cosi Fan Tutte” — they’re all like this — is the punch line.

A single set full of backstage clutter is all this production needs, and only the four straight chairs arranged in a row at center stage are used. From time to time, large, silent-movie-type explanations of the action are projected on a big screen on the back of the stage where the “orchestra,” a string quartet and a piano, holds forth.

Soprano Melissa Chavez was a winning and sympathetic Florrie. Teetering on the edge of sophistication, her Ohio-ness wins out when it matters and her struggles with her virtue come across as quite real. Mezzo Erin Passmore grew in the role of the frumpy Dorrie, daring to take some chances. Tenor Samual Keeler’s Randy seemed undefined as a character but managed well vocally, but Sean Pflueger as Elmo struggled all evening with both pitch and a wooden, unfocused stage presence. Both bass-baritone Sasha Olinick as Don Fonso and soprano Randa Rouweyha as Tina (a holdover from the 2009 production) were outstanding, vocally and dramatically.

With the “orchestra” behind the singers, there were moments that the large ensembles were sort of a mess, but Stanley Thurston conducted sensitively and incisively, helped immeasurably by pianist Joseph Walsh’s expertly played recitative continuo.