NEW YORK – As you settle into your seat at Broadway’s “Bad Cinderella,” the subtle sound of piped-in birdsong greets you. Enjoy it while you can. The next few hours will be a frantic onslaught.

The show that opened Thursday at the Imperial Theatre is a hyped-up, over-caffeinated fractured fairy tale that loses its way in the forest and wastes some of the nicest melodies Andrew Lloyd Webber has written in decades. It’s lewd and smugly arch and increasingly tiresome.

The titular star — a fine Linedy Genao — plays a so-called rebel in the beauty-obsessed town of Belleville, set somewhere in a France that has bikini waxes and also swordsmen. She doesn’t wash her hair, eschews manicures and even spray-paints “Beauty Sucks” on a statue of Prince Charming. What a rebel! She is clearly the creation of old people.

The book by Emerald Fennell nominally tries to argue that conformity and surfaces are the enemy but doesn’t have the verve to finish that argument, ending up with a musical that would have been mildly progressive in 1995.

The lyrics by David Zippel can be seen coming a mile away. He’s the kind of guy who rhymes “Cinderella” with “salmonella” and “fault” with “assault.” Director Laurence Connor pitches everything at 11, a never-ending streak of ruffles, pectoral muscles and power singing.

The tone is set early, with a trio of milkmaids in low-cut costumes offering dairy that has been “squeezed by my hand” and a shirtless baker screaming “Hot buns! Check out my hot buns!” It sort of undercuts the show’s theme of empowerment when much of the material seems cribbed from a middle school boy’s imagination.

In this tale, the evil stepsisters act like Valley Girl airheads, the Godmother performs plastic surgery to make people look better and we have two princes — Charming, a “man’s man” who is “hot enough to blister” and his brother Sebastian, a “human sleeping pill.”

Broadway is awash with royalty these days, from “Six” to “Aladdin,” “The Lion King” to “Camelot” — and fairy tales were just on with “Into the Woods.” “Bad Cinderella” pilots a rocky course by wanting to tell a princess story with a non-conformist who then conforms.

Being British, it naturally also reveals a ton of psychodrama when it comes to royalty, ripping the institution whenever it can, from breeding and privilege to perhaps a dig at more recent events: “Nothing like the marriage of a prince to a commoner to give the illusion of equality and stop people getting all revolution-y.”

One bright spot is Carolee Carmello, who is simply perfection as the evil stepmother, rattling off insults with aplomb — “Gain one more ounce and you’ll be disowned!” — and offering a great duet with the queen, “I Know You.” Other standout songs include “Only You, Lonely You” and “Unfair.” But “Far Too Late” never seems to end and the trio singing “Moment of Triumph” step on each other.

There’s just too much here, from the over-the-top costumes to cast members milling in the audience, to the fog machine going into overdrive to men twerking onstage to a uselessly detailed map of Belleville slipped into the Playbill. “Oh my God, do you ever stop?” a prince even at one point asks Cinderella.

This is a musical that simply outstays its welcome, unable to finish, or as it likes to repeatedly joke, have a “happy ending.” You will long for the sound of birdsong.