Octavia Spencer’s natural charisma and trustworthiness are playfully subverted in this goofy Blumhouse-produced horror thriller, directed by The Help’s Tate Taylor. Sue-Ann (Spencer) is a lonely veterinarian’s assistant who befriends a group of 16-year-olds who talk her into buying them booze at a local store. Rather than allowing them to drink and drive, she suggests they use her basement as a makeshift bar, as long as they never go upstairs. “Ma’s” soon becomes the school speakeasy. Spencer is brilliant as the dreamy, socially awkward Sue-Ann, transformed from shy social media stalker into the rambunctious life of the party, blasting out Debbie Deb’s 1984 hit Look Out Weekend. Unsurprisingly, the kids become suspicious.

For about two-thirds of the film, there’s only the faintest whiff of anything truly sinister, with Taylor preferring to hint at what Ma might be hiding while refraining from gore and jump scares. Spencer mostly keeps her own craziness simmering too, until the film’s final act, at which point she is permitted to go batshit.

Cameos from Allison Janney and Juliette Lewis add a sheen of prestige, but those who enjoy Blumhouse productions for their unabashed silliness will be pleased to discover a sticky slice of schlock, with both household appliances and prosthetic genitals given their genre moments.