Oh, Follies. That Sondheim masterpiece featuring a killer score and troubled book. And last night, a one-night only concert of this work took place at the surprisingly handsome auditorium of the Francis W. Parker School to support The Humanities Festival. This concert, sponsored by Greta Wiley Flory in memory of her late husband Bill, a longtime friend and supporter of the Festival (isn’t that just so romantic?), featured some of the best musical theatre performers in the city.

I think most of us know the story: former follies performers come together for an ultimate mingle before their theatre is torn down. They relive some of their favorite follies moments, while four of them — the leads — choose to spend the evening haunted by ghosts of their unfulfilled dreams and bicker at each other. Talk talk talk, bicker bicker bicker bicker.

But you gotta know the territory.

Well, music director Doug Peck — who masterminded and assembled this evening along with his partner, and host for the evening, Rob Lindley — certainly knows the territory of Sondheim’s tricky score. Music direction, which featured (extremely) reduced orchestrations by Peck, was pristine. We had piano (played by Peck), bass, drumset, violin, trumpet and flugelhorn (the latter two both played by the outstanding Carey Deadman).

And the folks in the important roles knew their parts remarkably well, too. Well, at least the ladies did. Hollis Resnik made for a dark and emotionally raw Sally. Without notice, her voice would flip from kitten-esque purr to steely belt. While at times just a tad flat, I adored her “Losing my Mind.” I should also note that Resnik’s choice of outfit for this concert was perfect: a black tea dress with full skirt. Totally Sally. By comparison, Rebecca Finnegan didn’t bother to amend her ueber-contemporary look for the role, but her selling of Phyllis’s two songs (well, four if you count that she expertly performed a medley of Phyllis’s various follies numbers, including “Uptown, Downtown,” “The Story of Lucy and Jessie” and “Ah, But Underneath”) was exemplary. Exemplary, I tell you.

What else? Barbara Robertson gave an effortlessly giddy “Ah, Paris” (would love to see her take of Phyllis someday, too) and Peggy Roeder seemed to live every syllable of “I’m Still Here” (though she could cut back on the speak-singing — not so much a fan of that). And then there was Renee Matthews and Emily Rohm who give me chills (and tears) with “One More Kiss.” I haven’t heard that song performed so well…ever?

Another highly anticipated performer on my list was E. Faye Butler, who flew over from Washinton, D.C., where she’s starring as Aunt Eller in a landmark production of Oklahoma at Arena Stage, to sing “Who’s That Woman” and, as a surprise addition, “Can That Boy Foxtrot” … into her music stand. And this was the biggest problem with several of the performers on an otherwise lovely night: a white-knuckled dependence on the lyric books. A little more familiarity with Sondheim’s score by these secondary performers (and the leading men) would have been nice.

Oh, I’m being such a picky bitch. For a one night concert with probably very, very little rehearsal, it was fabulous.