Ma is a rare gem of a horror film. Its cast is award-winning and its premise is promising, but despite this pedigree it never takes itself too seriously.

Maggie and her mom Erica (Diana Silvers and Academy Award nominee Juliette Lewis) are moving back to mom’s hometown after a divorce. We get hints through their car and some side comments that this move is a big step back for both of them, but that’s not the story we’re being told here. Maggie goes through the regular motions of trying to make friends at her new school, and she gets adopted into a small clique of the cool kids who drink on weekends and get to use Andy’s (Corey Fogelmanis) dad’s van.

One day, while hanging outside a liquor store asking random of-age passersby to buy their booze, they hit the jackpot. Sue Ann (Academy Award winner Octavia Spencer) is a nice lady in scrubs who agrees to help these kids out. She remembers being young once and wants the kids to have the same fun she did. Or, at least that’s what she tells them. If she were a creepy old guy, this exchange would come across as far more unsettling than it does, but with her friendly face and Facts of Life hair, the teens can’t even imagine Sue Ann a threat.

Slowly, Sue Ann draws the kids into her world. First she gets them the booze. Then she lets them drink in her basement. Next, she makes them pizza rolls. When she starts inviting their classmates over to party and puts herself in the center of the dance floor, both Sue Ann and the kids think that they’ve found their Shangri-La. But nothing can be this fortuitous, and Sue Ann’s devious plans begin to surface all around her.

The horror stacks up high within Ma. Just when you think you may have nailed down precisely what’s going on with Ma (as the kids call Sue Ann), another layer is heaped on the pile and the film shifts into a new version of hell. Childhood trauma, mean kids, abduction, torture, and forbidden locked rooms are just some of the less spoilery facets of the film. These pivots within the scares never come across as jarring. Thankfully, the movie somehow maintains a playful tone which makes the increasingly ludicrous all part of the fun

Best of all, the entire cast seems to be in on the joke. Luke Evans and Missi Pyle each play to a caricature that can be found in a Lifetime movie and revel in the roles. Academy Award winner Allison Janney even has a teeny part as Sue Ann’s boss. In any other movie, with any other actress, it would be a throwaway part, but Janney makes the comic relief memorable. Through all of the performances, however, Spencer is the pillar holding up the entire film. Her measured desperation and hunger for acceptance are always simmering below the surface of her barely collected act. When Ma can no longer contain her darkness, Spencer’s full commitment to the role crescendos, elevating Ma into the pantheon of satirically aware but still quite insane horror.

The film’s smörgåsbord of a plot and blend of humor and horror could have easily been a failure on all fronts. Instead, we have the rare example of ambition and commitment coming together wonderfully.