The law of diminishing returns is in full effect here, and the franchise is wearing out its welcome, but let’s face it: any movie that features Jessica Biel as an ass-kicking vampire slayer and Parker Posey--yes, Parker Posey!--as a vamping vampire villainess can’t be all bad, right?

Those lovely ladies bring equal measures of relief and grief to Blade, the half-human, half-vampire once again played, with tongue more firmly in stone-cold cheek, by Wesley Snipes. With series writer David S. Goyer in the director’s chair, the film is calculated for mainstream appeal, trading suspenseful horror for campy humor and choppy, nonsensical action.

The franchise still offers some intriguing ideas, however, including Drake (Dominic Purcell), the original vampire, whose blood contains the secret that could destroy all blood-suckers in a plot that incorporates a sinister "blood farm" where humans are held--and drained--in suspended animation.

And Biel’s wise-cracking sidekick (Ryan Reynolds) in her cadre of "Nightstalkers" provides comic relief in a series that’s grown increasingly dour. All of which makes Blade: Trinity a love-it-or-hate-it sequel... supposedly the last in a trilogy, but the ending suggests otherwise.