Little Monsters is the perfect crowd-pleaser of a zombie film: filled with righteous gore, excellent violence and… a classful of kindergarteners?

That’s the unlikely spin Abe Forsythe‘s film takes on the well-worn zombie genre, and it works shockingly well, delivering a horror comedy that’s part Zombieland, part School of Rock. Little Monsters opens by taking great pains to assure us that our protagonist Dave (Alexander England) is not a good person. He gets in screaming matches with his girlfriend on her birthday, takes advantage of his big sister Sara’s (Nadia Townsend) generosity and proves to be an astoundingly bad influence on his young nephew Felix (Diesel La Torraca). After a breakup that he frankly has coming to him, Dave is sleeping on his sister’s couch, playing too many video games, jerking off to VR and not doing a whole lot else – until he meets Felix’s kindergarten teacher Miss Caroline (Lupita Nyong’o), who inspires him to volunteer as chaperone for a class field trip, mostly so he can try to get into her pants.

Unfortunately, the petting zoo the class visits is next door to an army testing facility, and pretty soon the kids, Dave, Miss Caroline and a childhood entertainer moonlighting as a complete psychopath named Teddy McGiggles (Josh Gad) are stranded in the petting zoo’s gift shop, surrounded by hundreds of extremely gnarly zombies.

Nyong’o is so phenomenal in this film, a beacon of movie star charisma.

Miss Caroline’s a remarkable teacher and very cool human whose students all adore her, partly because she teaches them life lessons in the form of charming ditties she writes and performs on her ukulele (Nyong’o has a lovely singing voice). Once stuff goes sideways, she manages to keep them all calm and safe in the midst of a horrifying zombie attack through no shortage of heroic measures. She’s funny and fierce and warm, and it’s easy to believe that mere proximity to Miss Caroline has the capacity to turn Dave from a piece of shit into a decent person.

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Because England is really great, too, selling Dave’s journey from slacker to hero equally convincingly. Gad plays both into and against type as Teddy, annoyingly perky in character and downright disturbing when the cameras are off. But the kids are the real achievement here, since movies often seem to have a hard time finding one believable child actor, and Little Monsters has fifteen. Felix, in particular, is one of the cutest onscreen kids in recent memory.

This movie’s just such a fun, funny, gross, good time. It’s a refreshing combination of sweet and distasteful, with gleefully uncool (yet no less effective) needle drops including Taylor Swift, Neil Diamond and Hanson. It’s got a great look and bracing energy, leaving not a single moment for the audience to get bored of this goofy little gimmick.

There are so many great gags in Little Monsters, both of the bloody and funny variety.

But amid all the gore and the silliness, the characters – not the gags – drive this story, and that’s why it’ll stay with audiences longer than the typical fun but forgettable zombie romp.