A good movie is often hard to find. A Broadway version of that movie is an even dicier thing. And a movie version of that? Well, now you're just playing with fire. But sometimes the gambit works: For example, the effervescent "Hairspray" or more recently “The Color Purple,” which is big-hearted with its songs, themes and storytelling but also a different experience than the 1985 Steven Spielberg movie.

Then there’s “Mean Girls,” which kind of doesn’t really know what its point is.

The new musical (★★½ out of four; rated PG-13; in theaters Friday) doesn’t really reproduce the stage show as much as it is a TikTok-themed redo of the 2004 Lindsay Lohan teen comedy – a film that was just fine the first time, thank you – with a smattering of show tunes. It’s not a bad thing, really, but mainly feels like an unnecessary one.

Just like the first time, Tina Fey writes and also appears in this “Mean Girls,” which centers on new North Shore High School student Cady Haron (Angourie Rice). Formerly homeschooled in Kenya, she’s thrown headfirst into the linoleum jungle of hormones and cliques.

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Cady first befriends lovable outcasts – and the movie’s narrators – Janis (Auliʻi Cravalho) and Damian (Jaquel Spivey), who warn her to stay from the popular Plastics, run by the imperious Regina George (Reneé Rapp).

Regina, whose entrances are as dramatic as a James Bond movie intro, invites Cady to lunch with her minions, painfully insecure secret-keeper Gretchen (Bebe Wood) and delightfully ditzy pal Karen (Avantika). Janis and Damian want Cady to hang out and get dirt on the Plastics, but when Cady develops a crush on Regina’s ex Aaron (Christopher Briney), the claws come out between frenemies and, yes, someone still gets hit by a bus. 

The new “Girls” sticks to the script plotwise, to a slavish degree. Even Fey and Tim Meadows playing their old teacher roles seem forced and uninspired. It’s only when the movie remembers it’s a musical that it refreshingly breaks from the norm.

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The ultra-peppy tune “Revenge Party” is the most joyous thing ever to reference putting someone’s head on a spike yet also nicely moves the plot along as Cady and Janis’ montage-y plan against the Plastics takes form. And songs like Regina’s “World Burn” and Janis’ “I’d Rather Be Me” bring both entertaining zest and key character moments courtesy of strong turns from Rapp, who reprises her Broadway role, and Cravalho, the powerhouse voice of Disney’s “Moana.”

But they’re also ringers that make it obvious how, in this new take, some of the characters overshadow the conventionally drawn Cady. Arguably, Lohan’s best performance was in the first “Mean Girls,” giving Cady a magnetism that Rice doesn’t have. That said, the new movie is pretty much designed to be the Regina George Show.

Rachel McAdams brought a chilly malevolence the first time around but she was on equal ground with Lohan – Rapp, on the other hand, is a force of nature, like Cruella De Vil crossed with Marilyn Monroe. Not only does she hungrily chew at all the scenery, she’s taller and more physically imposing than all the other girls, which adds to a number like “Apex Predator” and gives her a cool menace.

Directed by Samantha Jayne and Arturo Perez Jr., “Mean Girls” 2.0 has its clever moments, with a new emphasis on the infamous Burn Book, Jon Hamm in coach shorts, a couple of fun cameos and one truly outstanding riff on “iCarly.” But compared to the original, one of the most iconic teen flicks of this century, it’s rather inessential.

Or, to borrow a “Mean Girls” phrase: Stop trying to make “fetch” happen because it already has.