This is essentially a campy, blood-soaked, Troma-type horror film -- the sort of subject matter normally found in a schlocky direct-to-video opus, but realized with a decent budget and a capable cast of recognizable actors, including Nathan Fillion (SERENITY) and Michael Rooker (HENRY PORTRAIT OF A SERIAL KILLER). The slightly schizophrenic advertising campaign promised both laughs and genuine horror; the former are reasonably abundant, but that latter is negligible -- because you just can't take it seriously.

Writer-director James Gunn (who penned the script for the DAWN OF THE DEAD remake) begins with a quote from THE BLOB (a meteor falls to Earth, bringing a monster) and then just keeps on quoting from just about everything: NIGHT OF THE CREEPS, David Cronenberg's SHIVERS and THE FLY, George Romero's NIGHT OF THE LIVING DEAD and DAWN OF THE DEAD, Wes Craven's DEADLY BLESSING and/or A NIGHTMARE ON ELM STREET, sexually violent Japanese anime like UROTSUKIDOJI, and even -- strangely enough -- A STREETCAR NAMED DESIRE.

You get to see a tiny slug-like thing burrow into Rooker's chest. Then he starts to mutate like Jeff Goldblum's Brundlefly. He impregnates a woman who blows up to the size of a weather balloon -- and then blows up literally, spewing forth a mass of slightly larger slug-like monstrosities that nose-dive into people's mouth's turning them into zombies, who soon take over pretty much the whole town while a small band of survivors seek to nip the alien invasion in the bud before it can spread to the rest of the world.

If all this sounds like outrageous rip-roaring fun, don't get too excited. The first act moves along with far too measured a pace as Rooker succumbs to the alien mutation. The scenes cannot sustain themselves because the necessary audience empathy is lacking -- we know we're just sitting through a slow build-up, waiting for all hell to break loose. When it finally does, the film delivers on some of its promise, but it takes too long to reach the point where things turn manic.

Unlike Gunn's script for the DAWN remake, this script reduces characterization mostly to broad strokes; there are some quirky bits that lend comic relief, but it's pretty clear from the beginning that this is mostly a "shooting gallery" cast of victims that we're not supposed to care about much, except for the leading lady and leading man. There is little sense of credibility, because that would stand in the way of the fun: if we really believed this stuff, it would be horrible, but if we know we're just watching a movie, we can sit back and scream with laughter.

The result is a cult movie all the way -- basically, a Troma film with a bigger budget (in case we miss the parallels, Gunn underlines them by showing a clip from THE TOXIC AVENGER). There are lots of outrageous special effects and gore; some of it's disgusting, but none of it is really scary, because the whole thing is far too silly, and the Gunn lets you know he knows you know it's silly.