starstarstarstar-outline(3 stars)

People who, for Lord knows why, hold musicals in low regard, please pause right here. This notice will be of little use to you. No, the appraisal of the Netflix adaptation of “The Prom” — a movie that is not merely a valentine to musical theater but also a sparkly gift wrapped in a Christmas, Hanukkah and Kwanzaa-appropriate bow of undying devotion to Tony nights and Playbill collections — is reserved for the die-hard keepers of the show tune flame among you.

Why? Because “The Prom” is a campy, sentimental slab of Broadway cake, with an order of jazz hands and high kicks on the side. It comes complete with a Dance at the Gym — and if you don’t know the historic significance of that allusion, well, I’m just sorry for your loss. It also features: Nicole Kidman as a leggy chorus girl with a heart of Fosse-engraved gold; James Corden, playing a Broadway veteran fluttering about in a silver tux with the panache of a middle-aged Liberace; Keegan-Michael Key, as principal of a Midwest high school and (straight) musicals superfan . . . and — ta-da! — Meryl Streep in the hog-the-spotlight role of a scenery-chewing stage star who never met a fawning admirer she didn’t desperately need.

Me? I wept at regular intervals.

Directed by Ryan Murphy with a “Glee”-tastic affinity for big numbers staged in school corridors, “The Prom” streams to your home at an ideal moment. I’m not talking about the holidays; I refer instead to the nine-month-long drought in being able to sit in a theater and watch a show in which stories unfold with actors improbably bursting into song. Who cares if the voices of almost everyone in the film sound as if they’ve been sweetened by magical elves? “The Prom’s” love of the industry it embraces and sends up — the theatrical arcana include a joke about the Drama Desk Awards — carries an exhilarating whiff of the classic, buoyant Hollywood musical comedy, “Singin’ in the Rain.”

That is a very good thing, and it makes “The Prom” a very dear thing. Lovers of musicals will groove on the shamelessness of its footlights worship. The numbers by Chad Beguelin and Matthew Sklar — all filmed in hazy pink and purple lighting — and the story by Beguelin and Bob Martin originate from the 2018 stage version that ran respectably on Broadway for 309 performances. That production, directed by Casey Nicholaw with a cast including Beth Leavel, Brooks Ashmanskas and Christopher Sieber, had a comfortably goofy comic charm and an eye on identity politics: The show turned on the fight by a gay Indiana teenager, played by Caitlin Kinnunen, who has been banned from her high school prom.

The conceit remains the main plot-advancer of the splashier movie, with enormously appealing Jo Ellen Pellman as Emma, who wants her date to be cheerleader Alyssa (Ariana DeBose). The “Footloose” setup casts an Indiana town as Backwater, USA, where the homophobic locals (led a bit unbelievably by Kerry Washington as Alyssa’s intolerant mom) stigmatize and isolate Emma. “We’re going down where the necks are red, and lack of dentistry thrives,” sing the Broadway swells who arrive on the wing of a scheme, to fight for Emma and earn good press for themselves.

“We are liberals from Broadway!” declares Andrew Rannells, in a funny turn as an actor between bookings who bursts in on a local PTA meeting with the rest of the hyperbolically dismissive New York contingent.

Nicholaw is retained as choreographer, and his jet-propelled dances here correspond to the warp speed at which his mind worked on Broadway in this and other projects, such as “Mean Girls.” Although I will acknowledge it stretches credulity in weird ways when insensitive students who bully Emma in one scene dance like Tommy Tune in the next.

Oh, what am I saying? It’s a musical!

It’s also fun watching Streep and Corden ham it up; You can imagine Murphy off-camera shouting: “Okay, let’s do it again, but bigger!” Kidman and Rannells get the best numbers, hers a performance lesson in adding chemistry to technique, called “Zazz”; his a production number in a mall, “Love Thy Neighbor.” You learn here, too, that comic actor Key can sing. Could we cast him in a musical when things return to some semblance of normal?

Meantime, I’ll stream “The Prom” a couple more times, maybe invite my daughter over to watch with her boyfriend, because I think they’ll like it, too. But I’ll try not to blubber then.

PG-13. At area theaters; available Dec. 11 on Netflix. Contains mature thematic elements, some suggestive and sexual references and strong language. 132 minutes.