Some mystifying, deceitful impulse has prompted Universal to misrepresent "Psycho II" as a sequel to Alfred Hitchcock's classic shocker of 1960.

Actually, it is more likely that moviegoers lured to the opening engagements this past weekend felt they were actually seeing a wacky-tacky pilot film for TV's first situation slasher comedy. A more appropriate title would have been, in the following order of preference: "Hey, Psycho!," "Norman, Is That You?," "Mother, Where Are You?" and "Always a Vacancy."

The producers seem to have the format fine-tuned already; they've decided to pep up the ingredients extracted from Hitchcock's endearing oldie with a little tactical seasoning from "Alice," "The Odd Couple," "Too Close for Comfort" and "Love, Sidney." Perhaps Tony Randall eventually will replace Tony Perkins in the lead, since the years have, sad to report, left Perkins far too weathered, hesitant and woebegone.

Released from a state asylum after 22 years of confinement, mild-mannered, split-personality, mass murderer Norman Bates returns to the scene of his appalling crimes enjoying a clean bill of mental health from a fearlessly sanguine psychiatrist. Taking up residence at the haunted Bates mansion, Norman gamely tries to get by in the pinched recession by juggling two jobs; he resumes management of the rundown Bates Motel (and even starts to give it a fresh coat of paint--canary yellow--before being distracted) while sharing in the hectic camaraderie of a diner across the road as a part-time short-order cook.

If the formula catches on, Norman's well-meaning but often bumbling attempts to rehabilitate himself and make friends (maybe even a girlfriend or companion in the person of Meg Tilly as a waitress) will be threatened in each episode by the harassment of bigoted louts and vindictive troublemakers, who persist in dredging up recollections of that earlier unpleasantness on the Bates' property. "It's starting all over again!" Norman will complain, cueing an outbreak of hysterical slashings and head-bashings.

The ingenious, mischievous twist (sort of in the spirit of Hitchcock's old half-hour TV series) is that the homicides will go unsolved week after week, since no one will be able to tell for certain whether Norman has suffered a relapse, his mother has been reincarnated or some brand-new schizos are on the loose.

Although "Psycho II" is obviously a travesty masquerading as a sequel, it's impossible to tell how deliberate the ludicrous aspects of the masquerade were meant to be. In fact, the best sustained mystery element of the show derives from stylistic sloppiness and confusion.

There wasn't the slightest advance indication that director Richard Franklin hoped to fabricate a sequel that would reduce spectators to such rollicking derision in the first 80 minutes or so that they couldn't help snickering at the murder spectacles, which pile up in a rather congested fashion during the final quarter-hour. Franklin, an Australian who studied film at the University of Southern California, has more or less specialized in thrillers back home; "Psycho II" suggests he's already burned out from overspecialization. Interviews quote him as hoping to duplicate the blend that supposedly made "Psycho" indelible when he saw it at the age of 12: "part horror film, part gothic melodrama and part black comedy, all mixed together."

Perhaps Franklin is just a defective mixer. For example, it's evident that someone is trying to be funny when Perkins sits down at the pianoforte for a few bars of "Moonlight Sonata," or when Tilly, a guest at the Bates mansion, is shown sitting up in bed reading "In the Belly of the Beast" with a chair shoved under the bedroom doorknob. But is there really anything witty or clever about gratuitous jokes of this ilk?

Resurrecting "Psycho" presupposes a considerable obtuseness, because you're obliged to pretend that no one has been playing variations off this extremely influential model for the past two decades. On the contrary, spoofs of the most sensational aspects of the original, particularly the notorious murder in the shower, have become commonplace, and we have the example of at least one filmmaking career, Brian DePalma's, that owes an ongoing obsessive inspiration to "Psycho."

Moviegoers with adequate memories will notice that the original shower episode has been sliced into a choppy condensation and further diffused by some inexplicable fiddling with the soundtrack. Unless my ears deceive me, the track has been redubbed in an oddly tinny, muffled way. However, the fundamental distortion is dramatic. There were only two murders in "Psycho," but moviegoers were sincerely alarmed by them because Hitchcock and screenwriter Joseph Stefano had taken pains to guarantee identification with the victims. The most striking--and, if you care to brood about it, disturbing--difference between the prototype and the sequel is that audiences now tend to react to arbitrary but spectacularly hideous murder scenes with laughter and applause.

And why shouldn't they? The depiction of murder is largely a virtuoso competitive event at the movies. The success of "Psycho" probably sparked much of this dubious invention by raising the ante on acceptable box-office standards of horror. But Hitchcock's murder interludes were triumphs of sadistically suggestive editing rather than sadistically graphic depiction. It is dismaying to see that viewers have no emotional stake in any potential victim in "Psycho II."

If Franklin had any respect for the source material, he might feel a little protective and avoid outrages as conceptually, as well as literally, nasty as the treatment of Vera Miles' character. "Psycho II" transforms her once sympathetic, heroic supporting role into a hateful bit part and then kills her off with a revoltingly obscene flourish. Has movie storytelling broken down this grotesquely in 23 years?

In retrospect the expository preamble to the first murder in "Psycho" seems extraordinarily detailed, involving and disarming; the impact of the killing wouldn't have been as stunning if Hitchcock hadn't invested 45 minutes of effective exposition leading up to a shocking payoff. At the time it was considered a big, perverse surprise to cast the top-billed member of the cast, Janet Leigh, as the victim, but the enduring shock derives from the illusion that you share her vulnerability--and then the subsequent vulnerability of Martin Balsam as the cagey but ill-fated private eye who investigated her disappearance.

Franklin wastes an elaborate amount of awkward derivative motion imitating Hitchcock's compositions and camera angles from "Psycho," especially the overhead angles, now exaggerated to stratospheric heights that suggest deliberate parody.

When Perkins scampers down the stairs and out of sight at the bottom of the picture frame at one point, is the sound defective or are we meant to jump to the unwarranted conclusion that clumsy Norman has fallen downstairs? It damn well sounds like he's taken a header.

The suspicion of wholesale miscalculation or ineptitude carries more weight when a director's touch lacks flair, consistency or sense. Franklin inserts a tilted frame at one point in imitation of a shot from "Psycho," and the tilt was so extreme that it looked like there must have been an earthquake. Not exactly, but "Psycho II" certainly goes out of its destructively derivative way to make "Psycho" go tilt. PSYCHO II

Directed by Richard Franklin; written by Tom Holland; director of photography, Dean Cundey; production designer, John W. Corso; edited by Andrew London; music by Jerry Goldsmith; executive producer, Bernard Schwartz; produced by Hilton A. Green for Universal Pictures. Rated R; 113 minutes. THE CAST Norman Bates....Anthony Perkins Lila....Vera Miles Mary....Meg Tilly Dr. Raymond....Robert Loggia