The horror-fantasy-sci-fi genre is crawling with directors who know the horror-fantasy-sci-fi genre, Joe Cornish being one of them. His audacious debut feature, "Attack the Block" -- in which lower-class youths from a London housing project do battle with man-eating aliens -- combines the wry nastiness of "Gremlins" and "The Thing" with such siege dramas as "Assault on Precinct 13" and "Escape from New York."
All this makes for a tautly wound take on the old B-movie as nationalistic metaphor. The downside? That the more the viewer knows about the genre, the better he or she will like the film, because character isn't Cornish's strong suit, and nobody here is particularly warm and cuddly.
It doesn't help that the main characters are thugs, which makes the timing of this independent U.K. film notable; thinking about the recent street violence in London will be unavoidable, given that our heroine, Sam (Jodie Whittaker), starts off by being robbed by the same hoodlums with whom she'll soon be helping fight intergalactic terrorists. Chief among the hoods is Moses (John Boyega), who does a terrific job of making his character convincingly dislikable. And who has a very personal approach to defending home (and, presumably, country) from slimy space fiends.
"Attack the Block" is essentially an action thriller and as such is effective. The humor, while considerable, is organic, rather than the result of Cornish going out of his way to make stupid gags. The kids sharply deliver Cornish's snappy dialogue, and there's an air of mystery about the movie and its creatures. This may have been due to its low-budget nature, but when it comes to horrifying abominations from the cosmos, less can oftentimes be more. Here it certainly is.