Spliced together from the murky preoccupations of horror flicks and B-movie histrionics (Aliens, Them, The Relic, Crichton's tampering with nature bugbear, etc.) Mexican director Guillermo Del Toro, who conjured up the curio-vampire Gothism of Cronos, has created a serviceable bugs-in-the-sewers routine.
Although his deeper ponderings on the morality of science get overshadowed by state-of-the-art gloopy nastiness in the dank tunnelscape of NY underground. The set-up is a chiller, as a freak plague attacks the children of Manhattan threatening to wipe out a generation. Enter sexy insect boffin Sorvino who sources the carriers to the city's cockroach population, genetically engineers a sly anti-roach roach (the Judas breed) and saves the day. Jump-cut to now, and something big, ugly and vaguely humanoid is prowling the underground, preying on ignorant commuters.
Squelch, squelch. It doesn't take Einstein to fathom that what previously was a cure has leapfrogged up the evolutionary highway and man is facing a seriously big bug problem. Re-enter scientist Sorvino, tortured by a Frankenstein syndrome, and disease-monitor hubby (Northam), sourcing the problem to some disused sub-subway and coming face-to-face with flying cockroaches the size of telephone boxes and a mask-like capacity to "mimic" humans.
Blood, screams, and CGI roaches chowing down on the supporting cast the net result, ensuring B-movie style pleasures with B-movie limitations. The script actually is not bad, the minimal science-as-doubled-edged-sword deliberations quite considered. There's even an occasional hint of satire; as jaded transport cop Dutton enters some slimy annexe of the hive, he bursts forth the familiar rejoinder: "This is some weird shit!" only for Del Toro's crafty camera to peel back to reveal just that; weird shit all over the walls.
Sorvino is fine, getting smothered in gunk and grunting through some sub-Ripley energetics, but Brit Northam finds the NY twang a fiercer opponent than the psychopathic creepies. It all descends, inevitably, into preposterousness, contrivance and eventually bare-faced silliness.