It’s a good thing Attack the Block opened in the UK back in the merry, merry month of May; its scenes of a squalid section of South London reduced to a flaming war zone may not play too well in British megaplexes given the current climate. On this side of the pond, however, where we’ve been watching reports of last week’s rioting with morbid fascination, the timing may in favor of this under-the-radar action-comedy wherein “inner city meets outer space.”

Not that it neneds controversy or cheap promotion to garner attention. A mish-mash of British irreverence, science fiction-horror tropes, and anarchic attitude give it a visceral punch, it walks a fine line between camp and horror.

It hits the ground running and maintains its breakneck pace throughout, first introducing us to a young nurse named Sam (Jodie Whittaker) who is mugged by a group of teenage thugs while on her way home. The gang, led by stone-faced tough Moses (John Boyega, a skilled young actor giving an impressive slow-burn performance), are interrupted by an extra-terrestrial arrival, and are forced to hand a beat-down to an ugly critter that has literally dropped out of the sky and landed in the middle of their housing project.

The creature is actually the first of a swarm of fierce gorilla-like ogres with inky-black fur and gaping maws of glow-in-the-dark teeth that would make a piranha envious that crash-land in a meteor shower and begin wreaking havoc. For reasons made clear in the final reel, the monsters converge on the group’s council house and they — along with Sam, pot dealer Ron (Shaun of the Dead‘s Nick Frost), and others — are forced to defend their lives and their turf with street smarts, improvised weapons, and mopeds.

First-time director Joe Cornish is an apparent fan of ’70s-’80s action-horror auteur John Carpenter and that era’s creature features, and patterns his film along the same lines. It’s equal parts Assault on Precinct 13 and Critters, with perhaps a little Warriors thrown in. Cornish keeps the story brisk, and sidesteps cliche in favor of characterization — and that’s where Attack the Block finds its gritty edge: Its hoodie-wearing hooligan protagonists are designed to be believable rather than easily likable, rendering them as true anti-heroes.