"Fort Apache, The Bronx" looks like a goner: the uptown variation on "Cruising." Each begins as a would-be topical, urgent police melodrama about the search for a homicidal maniac and then wanders luridly, absent-mindedly astray.

"Cruising" wallowed in the homosexual underworld of leather bars and sex clubs in Lowest Greenwich Village. "Fort Apache" -- now at area theaters -- exploits the troubled, blighted urban landscape of the South Bronx for picturesque squalor and gratuitous, grandstanding sensationalism. Not so coincidentally, both movies inspired organized protests by offended interest groups while they were on location.

It would be helpful if pressure groups were mistaken about the kind of dramatic license being indulged by invaders from Hollywood. But "Fort Apache" ends up confirming their worst suspicions.

At best, the filmmakers are guilty of wholesale confusion. For lamentable example, the plot degenerates into a hopeless tangle of loose threads and discarded hooks, beginning with the initial vicious teaser, which identifies Pam Grier as a drug-crazed prostitute who guns down a pair of unwary young patrolmen in their squad car.

Who could guess that the movie would imitate her M.O. -- weaving around the streets in a provocative daze, then vanishing, then reappearing for further injections of lethal playfulness, then suffering further lapses of memory and attention? The apparent femme fatale is transformed into so much excess baggage, no more essential than any other element in the melodramatic junkheap.

"Fort Apache" was the gallows-humor nickname coined by cops assigned to the 41st Precinct Station in the South Bronx, where years of arson, abandonment, creeping poverty and street crime reduced many blocks to a wasteland, resembling cities in the aftermath of a bombing attack. In the perhaps treacherous tradition of "The French Connection," the movie was suggested by the recollections of two officers, Tom Mulhearn and Pete Tessitore, who worked out of the 41st Precinct in the late '60s.

Paul Newman and Ken Wahl portray the fictionalized versions of these partners -- respectively, a gritty, wise-cracking veteran named Murphy and an easygoing young patrolman named Corelli. The film is meant to concentrate on their professional problems while interweaving off-duty human interest with romantic subplots.

Murphy, identified as the divorced father of three little girls (judging from a token appearance in one fleeting scene, they're too little for an actor of Newman's age), becomes involved with a young Puerto Rican nurse, Isabella, played by Rachel Ticotin. Corelli has a steady girl, Theresa, portrayed by the delectable Kathleen Beller. When introduced, these attachments are depicted in considerable detail in parallel scenes, leading one to expect an ongoing and perhaps effective contrast between the beat and the love affairs.

Yet even in the early stages, when etiquette demands giving the movie some time to develop, alarm signals keep going off. The episodes depicting police work play like a string of vaudeville blackouts. For example, there's no tension in the air when Murphy and Corelli save a jumper in the nick of time, or when Murphy tries to catch a fleet purse-snatcher or when he disarms a knife-wielding crazy by acting loony himself. The presentation always seems too superficial to inspire belief. Worse than that, the episodes seem calculated to throw showy bits in the star's direction. The cumulative effect of these bits is to trivialize the real world the movie is pretending to mirror.

Newman never seems at ease as Murphy: He struggles vainly to master a New York accent, to make sense of his misalliance with Ticotin (initially fetching, she begins to betray supercilious tendencies that turn her into an Hispanic Ali MacGraw), to survive the tinhorn heroism that afflicts the character after the filmmakers decide to promote him to holier-than-thou status among his fellow officers.

You're so conscious of Newman working to impersonate the overcalculated role of Murphy that Ken Wahl's effortless, ingratiating impersonation of Corelli looks slightly embarassing. Although the movie is contrived for the greater glory of the old pro, the kid keeps putting him to shame. Even the romantic priorities look unbalanced as the plot thickens and congeals. You never figure out what Newman and Ticotin are doing together, but Wahl and Beller are one of the sexiest young couples ever wasted by shortsighted filmmakers.

When the movie misplaces killer Pam Grier for prolonged periods, you forget about her terrible crimes too. The entrance of Ed Asner as a stern new precinct commander seems to signal a fresh dramatic situation, but Asner kind of drops out of sight.When he reappears -- supposedly overreacting to a demonstration by community activists -- you wonder if the dramatic focus will now be clarified.

No such luck. The script veers off in another direction, confronting the leads with a cut-and-dried Moral Dilemma when they witness a fellow officer chuck a kid off a rooftop. Their reluctance to blow the whistle is just the filmmakers being coy. It's an open-and-shut case of murder, with no possible taint of ambiguity to rationalize doubt or concealment on the part of the heroes.

The material is undermined by a lust for touching every provocative base in the neighborhood without doing dramatic justice to any of them. Unfortunately, Murphy's love affair is revealed to be a pretext for sordid and mawkish episodes that come flying like wobbly V-2s from left field, laying further waste to an already battered and addled scenario.

Faced with a renewed wave of protests from antagonized parties in the South Bronx (among other groups, the cops would have plenty to resent), a probable pasting from the critics and highly iffy popular appeal, the producers of "Fort Apache" would be well-advised to run up the white flag and prepare for a quiet, dignified retreat.