OK, now that they’re gone, let’s really talk. “What Lies Beneath” is a slick but surprisingly empty genre movie that builds to a not particularly shocking shock. As the movie opens, Claire Spencer (Michelle Pfeiffer) packs her daughter off for college and prepares to deal with empty-nest syndrome. Only her nest isn’t empty. Her second husband, a workaholic scientist named Norman (Harrison Ford), may be in the lab night and day, trying to work his way out of his famous father’s shadow. But a pretty young ghost (model Amber Valletta, who has about eight seconds of screen time) keeps dropping by to knock pictures off desks, fill the tub with water and play the stereo really loud. Claire is convinced that her next-door neighbor has murdered his wife, and does some pro forma “Rear Window” snooping. Is she on the right trail? What do you think? Even the movie’s marketing campaign makes it plain that the dead woman is actually someone Ford’s character had an affair with–“He was the perfect husband until his one mistake followed them home”–which renders the first hour of the movie pointless.

Not that it wasn’t close to pointless already. Ford and Pfeiffer are two of our chillier movie stars. Early in the movie, as they run through “cute” marital dialogue, they’re so stiff and unchemical it’s almost like watching a rehearsal. (He: “Wanna fool around?” She: “Yep!”) The scares, too, are shamelessly ordinary at first–an endless series of red-herring slams and bangs that are frightening only because the music is suddenly blaring. Boo! Nope, it’s only her husband. That kind of thing.

It goes without saying that Zemeckis (“Forrest Gump”) is far from a hack. “What Lies Beneath” is full of gorgeously pale and eerie images and, while the screenplay tends toward the obvious, the characters eventually get interesting. Still, it’s all in the service of banal moralizing about the misleading placidity of “happy” people’s lives. (What lies are beneath! Get it?) Zemeckis’s movie may well be a hit because it entertains in a way we are used to being entertained. It is worth $8.50. It is not worth remembering.

What Lies BeneathDreamWorks Opens July 21