In the third installment of Sam Raimi's madly inventive Evil Dead series, the director sends his usual hero, the square-jawed wiseacre Ash (Bruce Campbell), back to the Dark Ages, where he comes on like a smart-ass cross between Indiana Jones and Mad Max. It's fun to watch Ash treat his medieval hosts, including the monsters, with brazen contempt (''Yo, she-bitch, let's go!''), and there are a few flashes of Raimi at his black-comic best. Still, there are major valleys between high points; Army of Darkness lacks the insane relentlessness that made the previous Evil Dead films such funny, original rides. C+

