Warning: This review discusses the plot and reveals the fate of certain characters.

Somewhere, in this morass of Blum House schlock, is an intriguing horror premise about a bullied girl in a small town who grows up, meets the teenage children of her tormentors, who are now the age she was when they sexually humiliated her, and befriends them with the intension of doing awful things to punish the parents by proxy. Throw in a sub-plot about her own meek daughter being medicalised and imprisoned at home so she won’t suffer her mother’s fate, and you’ve got the constituent ingredients of dark and disturbing psychological thriller with psychosexual seasoning.

But this is Blumhouse, a den of cheap thrills, so Ma has no greater ambition that to deliver a b-grade teens in peril picture, with an original, rambunctious ghoul at the centre – Octavia Spencer’s dead-eyed matriarch, capable of flipping from teen friendly good time girl to gun pointing psycho at the spin of a half-empty beer bottle.

Ma plays like a rushed affair; a movie that just about hangs together and ultimately hits all the necessary story beats, (though not always in the right order) but would have benefited from a more considered treatment and injection of all that all important horror staple, style.

Director Tate Taylor casts his movie well – Spencer and Booksmart’s Diana Silvers in particular, lifting their respective scenes with requisite fierceness and tenderness respectively, but the movie lacks a coherent through line, or any sense of incremental tension. It plays like an assembly edit, and consequently, there’s little left for the audience to do but passively sit and wait for the story to move toward its inevitable, bat-shit climax; a descent into tired torture porn staples.

We’re left with yet another movie that both asks for our empathy toward the socially awkward and ridiculed, while simultaneously making them disturbed lunatics with few redeeming features – the kind of people who drug kids with vet medicine and tell their daughter she’s dying of cancer. Still, at least Ma doesn’t forget to run over the obnoxious high school slutty prom queen archetype, so she’s mad but not all bad.