You can't swing a cat without hitting a Gertrude Stein happening in this city. The Summer of Stein sprouted two exhibits about the queer icon (and her family) at the Contemporary Jewish Museum and the SFMOMA; and now an opera production at the Yerba Buena Novellus Theater of the Gertrude Stein/Virgil Thomson collaboration, Four Saints in Three Acts, performed by the Ensemble Parallele team.
It's actually a dozen Saints, four acts (the last act is undeniable, "that's a fact") and two operas. The wrong arithmetic in the title should give you an idea that it does not all make sense, as it should with Gertrude. Two operas: Ensemble Parallele performed the 50s revised version of the Four Saints opera, which clocks in at a breezy 50 minutes, rather than the original, twice-as-long, 1934 version. So they pre-pended the work with a palimpsest by Italian composer Luciano Chessa (who teaches his craft at the SF Conservatory).