Two things about Artistry’s production of the Stephen Sondheim/James Goldman musical about a ’70s reunion of Broadway showgirls: It is not a perfect “Follies.” And there never has been a perfect “Follies.”

The 1971 Broadway original is now spoken of in hushed, reverent tones, but there was grumbling even back then. “Follies” is so rich it gets better every time you see it, particularly when you see new takes on its complex central characters. And the show is so hugely ambitious that it’s tough to nail all of its 10 zillion elements.

What Artistry gets dazzlingly right is Sondheim’s music, under the direction of Anita Ruth (full disclosure: she’s a pal). The 22 musicians listed in the program sound fantastic, in everything from the smoky sax that buoys Caitlin Burns’ thrilling delivery of the torch song “Losing My Mind,” to the tentative-then-triumphant brass of the showbiz anthem “I’m Still Here,” to the anxious strings that underscore tense dialogue.

Really, “Follies” is two musicals, starting with the reunion, where now-middle-aged showgirls from a Ziegfeld Follies-like production sing their hits for each other.

Two-thirds of the way in, that show explodes, becoming a Ziegfeld-esque extravaganza that takes place inside the nervous breakdowns of two unhappily married couples: brittle Phyllis/unfaithful Ben and deluded Sally/desperate Buddy, who express their ennui in the form of showstoppers that prove to be more reliable witnesses than memory (the singers are lying in the relatively realistic first section but, in the gonzo last section, they tell the painful truth). Oh, and those four are shadowed by their 1930s selves, who remind the mired-in-nostalgia couples of allegedly happier times.

This “Follies” starts slowly (that may change, since snow last weekend delayed its opening). Dancing is not its strong suit, although Myron Johnson’s choreography works hard, particularly in his witty use of “The Carol Burnett Show”-like boom-shacka-lacka boys in “Story of Lucy and Jessie.” It begins on a tarp-shrouded set that represents an abandoned theater but looks more like a drab hellmouth. Designer Eli Sherlock redeems himself, however, with a set transformation when the show explodes.

With a parade of one-song supporting characters, “Follies” can lose sight of its two couples, but the four leads are excellent, particularly Paul Coate’s subtle take on hapless Buddy. And director Benjamin McGovern has made strong choices that focus this “Follies,” including cutting the eminently dumpable “Rain on the Roof” and having the older quartet interact with their younger selves, which helps us see that their real folly is clinging to the past.

The show also hints at the folly of anyone waiting for a perfect evening of theater. Like life, it’s never perfect. The cool thing is that dozens of people are doing their damnedest to get there.