It’s the ultimate celebrity redemption tour, two decades in the making. In the annals of pop culture, few characters have undergone an image makeover quite like the Wicked Witch of the West.

Oh, she may have been vengeful and scary in “The Wizard of Oz.” But something changed — like, REALLY changed — on the way from the yellow brick road to the Great White Way. Since 2003, crowds have packed nightly into “Wicked” at Broadway’s Gershwin Theatre to cheer as the green-skinned, misunderstood Elphaba rises up on her broomstick to belt “Defying Gravity,” that enduring girl-power anthem.

How many people have seen “Wicked”? Rudimentary math suggests more than 15 million on Broadway alone. And now we have “Wicked” the movie, director Jon M. Chu’s lavish, faithful, impeccably crafted (and nearly three-hour) ode to this origin story of Elphaba and her (eventual) bestie — Glinda, the very good and very blonde. Welcome to Hollywood, ladies.

Before we get to what this movie does well (Those big numbers! Those costumes!), just a couple thornier issues to ponder. Will this “Wicked,” powered by a soulful Cynthia Erivo (owner of one of the best singing voices on the planet) and a sprightly, comedic, hair-tossing Ariana Grande, turn even musical theater haters into lovers?

Tricky question. Some people just don’t buy into the musical thing, and they should be allowed to live freely amongst us. But if people breaking into song delights rather than flummoxes you, if elaborate dance numbers in village squares and fantastical nightclubs and emerald-hued cities make perfect sense to you, and especially if you already love “Wicked,” well then, you will likely love this film. If it feels like they made the best “Wicked” movie money could buy — well, it’s because they kinda did.

Much credit for that goes to Chu, who has said he spent so many years working on “Wicked” that three of his five children were born during that span. Chu clearly has musical theater in his DNA, as we already knew from “In the Heights.” His actors don’t break awkwardly into composer Stephen Schwartz’s famous pop-show tunes: they run headlong into them, and sometimes blow the roof off with them.

Another question: Will people be turned off when they see “To Be Continued” at the end, after two hours and 40 minutes, realizing they must wait a year for Part 2? Also tricky. Surely this COULD have been one movie. But then, how would they have followed “Defying Gravity,” which brings down the Act 1 curtain (and the house) in the show? It’s hard to imagine just continuing with the plot.

Yes, the plot: We begin with Grande’s Glinda descending on Munchkinland in her glistening bubble, which since 1939 has been upgraded with a comfy sofa, to announce that, indeed, the wicked witch is dead.

But someone challenges Glinda: Is it true you were her friend? Well, er, yes, Glinda replies carefully. Their paths did cross — back at school.

Cue opening day at Shiz University. Glinda — well, for now, Galinda “with a ga” — an aspiring sorcery major, arrives in her pink suit looking like mix of Grace Kelly and Elle Woods. She already has a fan base and a private suite.

Erivo’s tour de force? That would be “Defying Gravity,” the show’s huge signature song, coming as the mood has changed into something far more ominous. Both young women are in the Emerald City, where they — or at least, Elphaba, have discovered that the wizard is not powerful and beneficent, but, more like, well, Jeff Goldblum — charming and weak, with a big, dark secret.
“So if you care to find me,” belts out Elphaba, having discovered the power of her broomstick, “Look to the western sky.” Where, exactly, is she going?

Hold that thought. For exactly one year.

“Wicked,” a Universal Studios release, has been rated PG by the Motion Picture Association “for some scary action, thematic material and brief suggestive material.” Running time: 160 minutes. Three stars out of four.