With a title like VAMPIRES VS. ZOMBIES you'd expect a battle royale of the living dead, the kind of monster-rally picture they don't make anymore. At the very least you can imagine a movie in which both vampires and zombies occupy a significant amount of the plot (or the screen) together. I'm guessing writer/director Vince D'Amato conjured a different scenario, since his 2004 film is a tepid vampire melodrama that attempts to be ambiguous and mysterious, but is simply confusing (or would be, if anyone gave a shit).
The movie kicks off with a WTF-inducing based-on-a-story credit by J. Sheridan LeFanu (note to D'Amato: just because your main character is a lesbian vampire named Carmilla doesn't entitle you to some royalty-free prestige; it does, however, make you look a clueless oaf) and progresses without the restraints of logic and cohesion. If D'Amato was interested in making a tamer echo of the myriad softcore girl-on-girl vampire flicks that'd be one thing, but by trying to "deepen" his film with a zombie subplot he accomplishes a whole lot of head scratchin' and not much else. Is this a pending-apocalypse set-up? From the precious little background D'Amato provides, it seems that only one radio station is aware of any zombie threat, and even they aren't exactly nonplussed. The zombie scenes themselves are brief clips arbitrarily shoehorned throughout the plot, feeling like an afterthought when somebody remembered the living dead were hot.
But even the limp vampire storyline suffers from an overall dearth of passion and conviction, as if no one involves in the production really cared (even the obligatory lesbian sex scenes lack spark). And if the director couldn't be concerned with his story and characters, why should we?