What Makes ‘Follies’ a Classic? 7 Answers and 1 Big Problem.

It was supposed to be a murder mystery: two couples, four motives, one gun. What it became was a different kind of mystery entirely: a musical that got prominent pans, alienated much of its audience and lost most of its investment — yet survived.

Not only is “Follies,” which opened on Broadway on April 4, 1971, still here 50 years later, trailing a string of revivals, revisals and gala concerts, but it is also now recognized as the high-water mark of the serious “concept” musical, that genre in which form and function are brought into the tightest possible alignment. The score, by Stephen Sondheim, is a marvel and a minefield of layered meanings. The sets make comments. And in the original staging, by Harold Prince and Michael Bennett, even frivolity had to serve a purpose.

Not that there was much frivolity in James Goldman’s script; the gun disappeared but the two couples were still floridly dysfunctional. Both wives had been showgirls in the Weismann (think Ziegfeld) Follies at the end of its run of annual extravaganzas in the years between the World Wars. Both had been in love with Ben, a Stage Door Johnny with big ambitions. But Phyllis was smart enough to nab him; they are now wealthy, unhappy sophisticates. Sally — romantic, conventional — got Ben’s feckless pal Buddy; never for one moment in the 30 ensuing years has she been happy with the trade-off.

During a Follies reunion at the decrepit Weismann Theater, on the night before it will be razed to make room for a parking lot, the two couples meet up and promptly disintegrate. As they do, their past selves appear alongside them as living characters. At the same time, former stars of the Follies relive memories and stumble through old numbers, magically ventriloquized from Broadway’s past in the Sondheim songs.

As the ghosts crowd in, the couples’ tangled history is unearthed, bringing them to the point of a group nervous breakdown in the form of a 30-minute mini-“Follies” of their own. To see them collapse, dissolving into a fantasy world accompanied by a Golden Age score, is to see American optimism collapse along with them.

But its big canvas is not the only reason “Follies” remains important. (See seven more reasons, and a caveat, below.) In its seriousness and cleverness, in its matching of style to substance, in its use of a medium to comment on itself, it has hardly ever been bettered. In any case, ambitious musical theater would never be the same; we would not have “Fun Home” or “Hamilton” or “Dear Evan Hansen” without “Follies” hovering behind them, the most beautiful ghost of all.

1. A requiem for nostalgia

“Follies” is about two lousy marriages. Mucking around among their mind games and betrayals, it more readily recalls midcentury drama than anything in the musical canon. (Imagine “Who’s Afraid of Virginia Woolf?” staged by Busby Berkeley.) But it’s also about the lousy marriage of American ideals and American reality, a union of near opposites polished and preserved by the shellac of nostalgia.

The brilliant concept was to use the two stories to inform each other, letting the Faulknerian past that is “not even past” intrude upon the present. So Sally’s ghost makes love to Ben while his makes love to her; later, she sings a torch song that sounds as if it’s from 1941. The reunion, if it reunifies one couple, destroys another. Even the songs we love are dangerous. That paradox is crystallized in “One More Kiss,” warbled by an ancient Viennese soprano while her younger self casually tosses off its coloratura. “Never look back,” the lyric warns. “Follies” is what happens if you do.

2. In praise of older women

The ghosts of Follies past that live in the theater had to be both ethereal and imposing. Casting was done among Las Vegas showgirls who were already six feet tall before their enormous headdresses turned them into giants. Even so, a Who Was Who of middle-aged and older women stole the show: Dorothy Collins, 44; Mary McCarty, 47; Yvonne De Carlo, 48; Alexis Smith, 49; Fifi D’Orsay, 66; and Ethel Shutta, 74, among them. Though cast for the kick of nostalgia their names elicited, they made survival itself seem vital and sexy, as Smith’s high-stepping Time magazine cover demonstrated.

3. Copies that improved on the originals

All of the performative songs in “Follies” — the ones sung as if they were real numbers from the past — are pastiches, sampling Harold Arlen (“I’m Still Here”), George Gershwin (“Losing My Mind”), Irving Berlin (“Beautiful Girls”), Sigmund Romberg (“One More Kiss”) and many others. With this catch: In almost every case, they are better crafted and richer than their templates. Which makes their salute to the past a wonderfully complicated, and sometimes cruel, gesture.

4. A number for the ages

Stella Deems, an old-school belter, had a specialty “mirror” number in the Follies. Now, at the reunion, she and six alumnae of the chorus line, including Phyllis and Sally, try to perform it, even though the dance (as one of them puts it) “winded me when I was 19.” Soon you see why, as the choreography, which at first involves simple poses and mirroring gestures, turns into an exhausting tap extravaganza, courtesy of Bennett. But the mindblower comes halfway through, when strange shards of spinning light emerge from the dark behind the panting, middle-aged women. These are the ghosts of their former selves: glamazons in mirror-encrusted costumes performing the number tirelessly and perfectly.

By the time the real and the remembered choruses merge in a thrilling finale, the idea of mirroring has taken on a larger meaning. “Lord, Lord, Lord, Lord, Lord!” Stella sings in wonder and horror at the person she sees in her looking glass. “That woman is me!”

5. ‘I’m Still Here’

De Carlo — a movie star of the ’40s and ’50s but Lily Munster to everyone thereafter — had the biggest name in the cast yet one of the smallest roles. She needed a showstopper; the one Sondheim originally wrote wasn’t working. During tryouts in Boston, he replaced it with “I’m Still Here,” a five-minute number that catalogs with tart good spirits a showbiz life (based on Joan Crawford’s) in which you “career from career to career.” It could not have been staged more simply: De Carlo basically just stood downstage and let it rip. Still, it was (and remains, in the many interpretations since) a knockout, driving home the point that long-term professional survival, and maybe emotional survival as well, is often a matter of inoculating oneself with failure.

6. The fabulousness

At $800,000, “Follies” was a very expensive show for its time, but you saw where the money went. Boris Aronson’s set, which exploded into lace and froufrou for the final sequence, was technically complex; Florence Klotz’s costumes were among the most sumptuous seen on a Broadway stage since Ziegfeld himself. And with all the major roles doubled by “ghosts,” the cast was huge: 47 performers, not including understudies and standbys.

“Nearly everything that could cause a Broadway musical to go over budget did,” says Ted Chapin, now the president of the Rodgers and Hammerstein Organization but then Prince’s apprentice — and the author of “Everything Was Possible,” a memoir of that experience. “If it were produced today, I would imagine it would log in at close to $30 million.” Alas, that’s a sum no one would spend on such a chancy show, which means we’ll never see its like again.

7. That poster

In 1971, the graphic artist David Edward Byrd was best known for his rock posters, including one for the original Woodstock and one for Jimi Hendrix. But he’d started designing for theatrical productions as well, and when an “aesthetic argument” led Prince to ditch one of his Art Deco-inspired sketches, Byrd came up with the now-famous face of “Follies”: an impassive beauty with flowing Technicolor hair and a branching crack from chin to brow. (The face was based on Marlene Dietrich’s, in a photo from “Shanghai Express.”) To Byrd, it represented the end of an era, but it also conveyed, with powerful concision, the crackup of an American fantasy of endless tranquillity. And, not incidentally, made a Broadway show seem as cool as Woodstock.

8. Then again …

“Follies” is brilliant and “Follies” is a mess. It bowls me over perhaps more than any other musical, yet I have never been fully satisfied with it intellectually. Look beneath the unparalleled packaging — the score, costumes, casting, staging — and you find a lot that doesn’t add up. As Frank Rich noted in his 1971 Harvard Crimson review, it’s “a musical about the death of the musical” — a wonderful paradox but one that undermines the experience. If musicals are dead … is this one too?

Sometimes — even when Carlotta sings “I’m Still Here” — the vaunted concept seems a bit opaque. (If it’s about her own life, how could it also be her Follies number?) And don’t look too closely at the main characters, either; spouters of self-conscious dialogue, they are only fully believable when they sing. For that, Goldman usually gets the blame — but if so, he should also get credit for providing the armature for everyone else’s epochal achievement. It may be about the death of musicals, but “Follies” pointed the way to bringing them back to life.