“Don’t bring a dumb date,” advises the promo slogan for “The Minus Man.” “Conversation usually follows.” Uh, huh. And I bet it starts with something like, “You still awake?” This movie started off pushing four stars…then just kept losing star fragments with each fraction of an hour that ticked irretrievably past. Vann Siegert (“Bottle Rocket”‘s Owen Wilson) is a boyish, clean-cut thirty-something drifter. Charming and affable with his James Spader looks and Bruce Dern drawl, he’s also a totally remorseless and chillingly random serial killer. A ride in Vann’s ominously rumbling black pick-up truck, a nip of his poison-laced Amaretto, and it’s off to the Big Sleep for you. (His first victim is singer Sheryl Crow. Well, not her, of course, but the languid junkie she plays. Add or subtract rating stars at your own discretion.) Vann takes a room in the home of Doug and Jane (Brian Cox and Mercedes Ruehl), a troubled middle-aged couple whose daughter is missing under somewhat mysterious circumstances. With Doug’s help, Vann lands a job at the Post Office where he meets Ferrin (the increasingly attractive Janeane Garofalo), an overeager lonely gal with a bit of a drinking problem. As he settles into a routine, Vann gradually ratchets up the killings, growing increasingly complacent as time goes by. When detectives, investigating a case seperate from his killings, begin snooping around the place, Vann faces what for him is a truly difficult decision: move on or indulge his fatalistic outlook and allow himself to be captured. If it sounds as if there’s a taut thriller at the core of Hampton Fancher’s film, it’s because there is. Sadly, however, he never allows that thriller to emerge. Instead Fancher, one of the many “Blade Runner” screenplay scribes, indulges himself far too much here and waters down a few truly creepy moments with a lot of unnecessary moody filler. That’s too bad, because he wastes solid performances by all concerned. Wilson’s conversational, self-analytical voiceovers double the horror of his secret life while Garofalo’s winsome desperation will make lonely guys everywhere raise their hands and cry out “Pick me! Pick me!” Or, um, maybe that’s just me. In any event, the film’s torturously plodding pace overwhelms the few positives sprinkled throughout, making “The Minus Man” an appropriate title, indeed.