Ma combines a Stephen King classic with a notorious true crime tale

Academy Award winner Octavia Spencer is no stranger to horror. She's had minor roles in the Kristen Bell-fronted sci-fi/horror flick Pulse, Rob Zombie's slasher sequel Halloween II, and Sam Raimi's witchy thrill ride Drag Me to Hell. But now, at long last, this diva is making her way into theaters as the title character of her own horror movie, Ma, which she's not only headlining but also executive-producing. And genre fans might squeal as this psycho-biddy thriller pulls some unexpected inspiration from an iconic Stephen King staple and one of the most twisted real-life murder cases of the last decade.

Before we dive into spoilers, here's the surface-level plot synopsis:

Ma centers on the unlikely friendship that sparks between a batch of party-loving teenagers and a middle-aged loner who lives on the edge of their small town. Charmed by the trouble-seeking teens, Ma (Spencer) agrees to buy them alcohol, then cajoles them into enjoying it back at her place. In her basement, the teens can blast music, booze it up, throw parties, and act like fools, as long as they don't break Ma's rules. But when new-to-the-crew Maggie (Diana Silvers) begins to suspect there's something sinister under Ma's smiles, it may be too late to save her friends.

SPOILERS below for Ma, including the ending!

Turns out Ma's invitation to Maggie and her friends isn't altruistic. Instead, it's a haphazard plot for Ma to get a bit of long-sought revenge. In unveiling Ma's malicious motivation, Scotty Landes' script pulls a few pages from Stephen King's Carrie. Flashbacks reveal Ma's high school years, when she was Sue Ann (Kyanna Simone Simpson), a sheepish dweeb with an impossible crush on the hottest boy in school. Like Carrie White, Sue Ann was mercilessly mocked by the popular kids, who would ultimately exploit her crush on a dream boy to embarrass her in front of all her classmates. In Ma, it's not a bucket of blood on prom night but rather a cruel slut-shaming prank in a janitor's closet. Still, it does the trick to trigger in Sue Ann a thirst for vicious vengeance.

Ma doesn't let these kids come over out of concern over their drinking in an unsafe environment, as she claims. She does it because she recognizes angel-faced Andy (Corey Fogelmanis) as the son of her teen crush/bully Ben (Luke Evans). And bonus, Andy's girlfriend Maggie is the daughter of Sue Ann's personal Sue Snell (Juliette Lewis), the popular girl who seemed like a friend but failed to save her from that pernicious prank.

However, unlike Carrie, Ma's desires are more complicated than bloodlust and fire, though they'll be plenty of both. Even after all he's done and all these years, Ma still wants Ben — and this leads to uncomfortable scenes of sexual assault once she's captured and chained up both him and his son. She kisses underage Andy, likely imagining this as a twisted redo of her high school sweetheart dreams with his dad. Then she attacks him when he fails to live up to her hopes. But Ben gets worse. She strips him naked, binds him to a bed where he's powerless to stop her, manhandles his genitals, threatens mutilation, then murders him. Still, her crush on him is so strong she chooses him over life itself. During the climax, when her party house is burning to the ground, Ma shuns escape; instead, she cuddles up to the corpse of the bully she loved. Like Carrie, Ma goes down in the flames alongside her bully.

Yet Ma is not only Carrie White. Shades of Carrie's mother are revealed along with Ma's secret daughter. The upstairs of Ma's house was always off limits to the teens. They learn why when Maggie discovers Genie (Tanyell Waivers) there. Like Mrs. White locking Carrie up in a closet, Ma locks Genie away on the second floor of her home, keeping her from her peers despite her pleas to join the fun. In response, Ma offers a variant on Mrs. White's classic caw of "They're all going to laugh at you." But Ma is not looking to protect Genie. As their story is unfurled, you can see where Landes plucked inspiration from an infamous true-crime case: the grisly mother-daughter tragedy of Dee Dee and Gypsy Rose Blanchard.

You might know their story from any number of true-crime podcasts, or the Buzzfeed article that inspired Hulu's limited series The Act, or the HBO documentary Mommy Dead and Dearest. In case not, here are the broad strokes: Dee Dee Blanchard was a seemingly jolly single mom who, in life, was praised for her tireless efforts to care for her paralyzed-from-the-waist-down, cancer-stricken daughter Gypsy. But once Dee Dee was found murdered in her home, and Gypsy did a perp walk without the aid of her wheelchair, a horrific lie was unearthed. Posthumously, Dee Dee was diagnosed with Munchausen syndrome by proxy, meaning she had been manipulating friends, doctors, charity workers, and her own daughter for years to convince them all that Gypsy was so sick that she needed her mother at all times. As Gypsy grew up, she began to rebel against her mother's domineering ways, and eventually, she had a hand in Dee Dee's death. Things for Ma and Genie play out similarly.

Like Gypsy, Genie uses a wheelchair in public, but she later shocks her peers by walking about with ease. A tense conversation between the single mother and her daughter suggests Genie suspects she's not sick as her mom claims. Like Dee Dee, Ma isolates her daughter from could-be friends to better keep her secrets. And in the end, Genie chooses to escape her mother, even when it means Ma's demise. In the battle of the basement, Ma is trying to kill her captured kids one by one. Then Genie joins forces with the attacked teens — and as Maggie stabs her mother, she flees with the others out the cellar door as the fire spreads through the house. Though she calls for her mom, Ma has made her choice, heading upstairs to the dead man in her bed.

Pulling from Carrie, Ma initially aims to earn audience sympathy for its titular psycho-biddy by unfurling a tale of an introverted teenager who was brutally abused by callous cool kids. But as its story spins into dark twists and violence, Ma's influences shift from antihero to abuser. Our view of her evolves through reveals of her mistreatment of her daughter, a shy teen girl in need of a defender, not another attacker. Ma pulls from iconic horror and real-life terror to tell a tragic and gruesome tale of how cruelty can twist the tormented into tormenters who are worthy of a horror story of their own.

The views and opinions expressed in this article are the author's, and do not necessarily reflect those of SYFY WIRE, SYFY, or NBC Universal.