“PATTI CAKE$”

*** 1/2

(R, 1:48)

Late in writer-director Geremy Jasper’s energetic directorial debut, “Patti Cake$,” a wealthy, powerful black male rap mogul, O-Z (Sahr Ngaujah), sizes up the overweight white girl who has just delivered his specialty cocktail along with a copy of her demo and a fervently performed original verse. “You’re just a culture vulture,” he sniffs. It’s an easy, cheap and devastating barb to lob at young Patti (Danielle Macdonald), one of many already hurled her way.

Rap has historically been an art form of cathartic resistance and liberation, created by oppressed black men to give voice, truth and emotion to their experience of the world. Using this inherently rebellious form allows those who are invisible in society to angrily bear witness to their existence and create their own representation, which is exactly what Patti is intending to do, and in this world, Patti needs liberating the most.

A lower-class girl from New Jersey, she’s discriminated against because of her size and gender; economic struggle has crippled her upward mobility. She’s body-shamed by the white men she crushes on, sexually shamed for her gender, hounded by collections agencies after payment for her sick grandmother’s medical bills.

It’s a culture bearing a particularly aggressive strain of white patriarchy, and rap stardom is her fantasy, her dream, her way out, but more importantly, her way of constructing herself. It’s Patti’s way to tell her own story and express who she is, to shed the nickname Dumbo and be Killa-P, or Patti Cakes, her grandmother’s nickname for her.

In “Patti Cake$,” outsiders create art away from the traditional structures of industry. During a gas station parking lot cypher with the local white rappers, Patti is violently head-butted after she schools them all. And trying to keep up puff for puff with the stoner black rappers in the local recording studio proves impossible. She ends up cutting a DIY demo (the songs are by Jasper) in a ramshackle structure in the woods with her group PBNJ, composed of her pharmacist best friend and hype man, Jheri (Siddharth Dhananjay); the local anarchist, Basterd (Mamoudou Athie); and the raspy-voiced, chain-smoking, wheelchair-using Nana (Cathy Moriarty).

Jasper’s cinematic style is wild and almost dizzyingly manic, using a handheld camera in extreme close-up and fast editing to pump the gas on this nearly out-of-control bus. It can be a bit off-putting at times, but he places the emphasis on Patti’s subjectivity. We experience the story through her — her point of view, her fantasies of stardom.

The apple doesn’t fall far from the tree. The actress and cabaret star Bridget Everett stars as Patti’s mother, Barb, a washed-up hair metal singer who gave up her band for her baby, whose only remaining moments of rock goddess glory are on the karaoke stage at the local dive bar. Everett is fabulous in this multilayered performance — Barb is heartbreaking and frustrating in equal measure.

The film belongs wholeheartedly to the incredible Macdonald — this is her star-is-born moment. But “Patti Cake$” is such a warm, generous and playful film, and so well-cast that every single character shines, particularly the newcomer, online discovery Dhananjay. “Patti Cake$” is a rousing and triumphant tale of freedom, creative expression, self-discovery, finding your voice — and actually being heard. Imagine that.