San Francisco Opera is offering a well-sung, sprightly account of Mozart’s “Marriage of Figaro.”

On Saturday’s opening night, even before the pre-performance announcement of “conductor to the pit,” the score of the Valkyries’ final series game flashed over the stage in the War Memorial Opera House, beginning an evening of high spirits.

Based on a 1778 play by Pierre-Augustin Beaumarchais, the opera is about love—namely, the love of the upper classes and their lower-class support teams. The main characters are Count and Countess Almaviva and their servants Figaro and Susanna, who are preparing for their wedding.

L-R, Slávka Zámečníková stars as Susanna and Peter Kellner is Figaro in San Francisco Opera’s “The Marriage of Figaro” onstage through Nov. 29 in San Francisco. (Cory Weaver/San Francisco Opera via Bay City News)

Wily, street-smart Figaro, valet and all-around fixer in the Count’s manor house, loves the boisterous, strong-willed Susanna, who serves the noble Countess. The Countess loves the Count, who in his own fashion returns the love, but has his roving eye fixed on Susanna.

The Count has promised to end the custom of “droit du seigneur,” which would assure his right to bed Susanna on her wedding night—give him just a week or so to work on it.

The libretto by Lorenzo Da Ponte takes class difference seriously; Da Ponte took pains to inform Emperor Joseph II that there was nothing offensive in the opera to worry about.

If some contemporary productions bring a mean-spirited tone to the stage, San Francisco Opera’s presentation of Michael Cavanagh’s 2019 version, set in post-revolutionary America and flawlessly directed here by Shawna Lucey, makes light of class division and much of romance.

Erhard Rom’s stately sets and Constance Hoffman’s period costumes depict 18th century grandeur. The American setting doesn’t chime in much; we are reminded of it briefly when the painting “Washington Crossing the Delaware” is reenacted onstage—a delectable moment.

Bass Peter Kellner in his house debut and soprano Slávka Zámečníková as Figaro and Susanna (in real life a married couple), ignite the proceedings from beginning to end. Kellner’s voice is as agile as his physical capering, and her high-flying soprano gleams with bright lines of lyric beauty. Both turn in commanding performances, Susanna emerging as the champion problem-solver.

L-R, Olivia Smith sings the Countess and Thomas Mole is Count Almaviva in San Francisco Opera’s presentation of Mozart’s “The Marriage of Figaro.” (Cory Weaver/San Francisco Opera via Bay City News)

As the Countess, soprano Olivia Smith brings home her two powerhouse arias with lavish vocal color and a warm stage presence. Thomas Mole’s more physical than vocal swagger is enough to carry off the role of the possibly reconciled-to-good-behavior Count.

Mezzo soprano Simone McIntosh is outstanding as the mischief maker Cherubino, her muscular, attractive voice leaving no doubt about her all-out search for love. Catherine Cook and Maurizio Muraro as Marcellina and Dr. Bartolo add hilarity as Figaro’s surprise parents, and Alek Shrader’s Don Basilio is an impressive busybody.

Conductor Sebastian Weigle in his San Francisco debut leads a performance that seemed muted at times, over-pressing at other times—imbalances that will improve as the run goes on. And the San Francisco Opera Chorus delivers its usual top-flight showing.

San Francisco Opera’s “The Marriage of Figaro” continues at 7:30 p.m. Nov. 3, Nov. 7, Nov. 10, Nov. 13 Nov. 18 and Nov. 27 and 2 p.m. Nov. 15 and Nov. 29 at the War Memorial Opera House, 301 Van Ness Ave., San Francisco. For tickets ($30-$456; $25 for Nov. 7 livestream), call (415) 864-3330 or visit sfopera.com.