In "Blue City," which is based on the novel by Ross Macdonald, the Turner boy (Judd Nelson), or perhaps I should say, "that Turner boy" -- he's full of trouble -- returns to Blue City, a sleepy town in Florida, after a five-year hiatus to find that his father, the mayor, has been murdered.

Kerch (Scott Wilson), a wily operator with some shady enterprises beyond the city line, has moved in with the mayor's wife, a busty seductress named Malvina (Anita Morris); they live in the mayor's old house, and high on the hog. That Turner boy figures it's pretty obvious who killed his pop, so with the aid of a corpulent, even wilier sheriff (Paul Winfield), an old school chum and the chum's sister (Ally Sheedy), he sets about settling old scores.

If it is useful to know that a director knows absolutely nothing about filmmaking, from script to casting to editing to where to put the camera, then there is one useful thing to be had from "Blue City." First-time director Michelle Manning has spun a yarn that is grotesquely implausible, less affecting than plausible, and less attractive than affecting -- "Blue City" seems to have been processed in mud, and even Godard at his most perverse couldn't have violated the rules of camera placement and framing more doggedly.

From the beginning, "Blue City" is a projection of tough-guy attitudes that fits its youthful actors like a cheap suit. The basic geometry of the script is carelessly conventional (it's not different from a TV cop drama, only longer), and while cowriter Walter Hill provides some moments that might have worked, had he held the megaphone, the dialogue is mostly the kind of ironic-and-doomed nonsense that adolescents might find quotable.

Sheedy, the distaff Steve Guttenberg, scales down the eye-rolling and neck-craning and jaw-waggling that are generally her version of acting, so we get to concentrate on the sonorities of her voice, which leaves you with a soft spot for spoiled brats everywhere. Sheedy's not inside any scene she's in, and in her "frisky" lovemaking with Nelson, she's on him like a piranha.

Piranhas with good taste, though, might shy away from Nelson, who tries out a Bruce ("Moonlighting") Willis riff -- the game show host as tough guy -- and ends up seeming like, well, Judd Nelson mimicking Bruce Willis. Nelson, a scrawny actor who ranges nimbly from the glower to the sulk, couldn't be more ridiculous in the action scenes (you think you're watching "Bananas"). There is a scene toward the end when the distinguished actor Paul Winfield, who seems to have been relegated to this sort of dreck, circles Nelson in the interrogation room and intermittently smacks him in the head. I bet he's never had an audience so completely with him.

Blue City, at area theaters, is rated R; it contains profanity, graphic violence and sexual situations.