Tin Cup.

RON Shelton, the writer-director of two baseball movies -- the good Bull Durham and the hapless Cobb -- has now made a golf movie, Tin Cup. Unlike baseball, which is highly cinegenic, golf is dubious movie material. Too slow, too laid-back, too ambulatory, it lacks the drama that has made, say, boxing stories a film staple. Shelton is aware that a golf film must, accordingly, include much else; so, as in Bull Durham, he gives us a romantic triangle: one woman and two dissimilar men. In Tin Cup, however, the difference is not in age and experience, but in character.

Roy "Tin Cup" McAvoy (spare me the explanation of his nickname) runs a ramshackle golf range outside a footling West Texas town with his sometime caddie, Romeo Posar. Roy was a terrific college golfer, but a combination of audacity and lethargy -- his "inner demons" -- has kept him from making it like his old school rival, Don Simms, now a PGA star. An attractive, urbane psychotherapist, Molly Griswold, comes to take lessons from Roy, who promptly, and for the first time seriously, falls in love with her. It turns out that she is Don's girlfriend, and quixotic Roy -- much against the warnings of his Sanchoesque partner, Romeo -- determines to make her his. How? Very simply by winning the toughest tournament there is, the U.S. Open.

So Roy, to pay a debt to his ex-sweetheart Doreen, the hard-as-cleats strip-joint owner, cedes his range to her: she, in turn, lets him run it, and even stakes his shot at the Open. No less bizarre is Roy's acceptance of a taunt from Don to caddie for him at an earlier tournament. But all this is less odd than Roy bullying his way into becoming Molly's patient, so as to declare his love to her. But I guess nothing is too far-fetched for a film whose double-entendre-studded dialogue does its utmost to sexualize golf, even if it stops at golfifying sex.

Kevin Costner is, after some recent errancy, quite winning as the shiftless hero, whose harebrained schemes almost invariably bogey. Yet his boyish charm endears him to women, to the point where his involvement with Linda Hart's over-the-hill and underwhelming Doreen is incomprehensible. Equally problematic would seem the casting of Rene Russo -- the large, raw-boned, nutcracker-jawed model-turned-actress -- as the wise and witty psychotherapist. Surprisingly, she proves more amusing and likable than one would have thought possible. Don Johnson is suavely snide as Don, and Cheech Marin is amiably wry in the rather cliched sidekick role.

Shelton and his co-scenarist, John Norville, steer somewhat uneasily between sophisticated comedy and simplistic fairy tale. Neither the golf nor the psychotherapy aspects ring true, even to the extent Shelton managed in his last two outings, Blaze and White Men Can't Jump. Thus the U.S. Open sequences strive for authenticity down to the presence of real-life sportscasters and golf figures, but then introduce details that should make the hero slink off the links in shame. As for William Ross's otherwise passable, mostly country-music score, it here espouses bombast that would have made Wagner blush.

As for the psychotherapy session and Dr. Griswold's general comportment, they strike me as a cross between the old Hollywood, with Sig Rumann as a Freudian travesty, and A. A. Milne. And what, in any case, is a psychotherapist doing in a godforsaken burg such as the I hope fictional Salome, Texas, with its Wellness Center where Dr. Griswold plies her unlikely trade? At least we see her with one other patient besides Tin Cup; at his driving range, she seems to be the sole customer.

On the credit side, there is Russell Boyd's cinematography, which neatly adapts itself to the story's shifting modes and moods. Boyd, an Australian, did yeoman's work with similar Texas scenery in Tender Mercies; he is particularly good at earth tones and the seductive spookiness of the golf range at night. The screenwriting, too, rises to moments of adult credibility, even if, at other times, the dialogue rattles around like sparse coins in a beggar's tin cup.

Seldom was there a movie as offensively inane as Jack, which makes even Big and Forrest Gump, its primary role models, loom like pinnacles of intelligence and good taste. The screenplay by James DeMonaco and Gary Nadeau is about as embarrassing as they come, but even greater blame must be accorded the star, Robin Williams, with whom in mind the two NYU Film School graduates concocted it. It is the story of a boy with a rare (actually preposterous) illness that makes him age four years in every calendar year, so that when he seems to be forty, he is really ten and queasily off to fifth grade. This after private tutoring from Bill Cosby, in an especially avuncular mode.

Robin Williams is an actor stricken with the not-so-rare ailment of charmlessness galloping in direct proportion to his attempts at ingratiation. With infrequent exceptions, his comedy is of the kind that makes right-thinking viewers want to strangle him, whereas his attempts at serious parts make persons of taste experience severe abdominal perturbation. Despite his fluky success, this flaky self-adulator and chronic overactor should be put out of, if not his, at least our misery. By us, I refer to those still able to keep their chins above the cloacal waters in which we are swimming, and whose pious wish will, yet again, be ignored.

Williams's gift for mimicry exists all right, but is submerged in the unstaunchable ooze of his smug enjoyment of it. He is like the party bore who laughs at his own jokes first and loudest, thereby making the laughter stick in his hearers' craws. Like a wet cake of soap, he evades his directors' control, and especially the grasp of a director such as Francis Ford Coppola, who seems pretty much to have lost whatever knack he once had. In Jack, actor and director bring out the sniggering worst in each other.

The running -- or, more properly, stumbling -- joke in the childish talk and behavior issuing from a grown man, wearying after a short while, is further undercut by one's never having really mistaken Williams for an adult. And the film doesn't strive even for superficial believability. Thus we see again and again Jack wriggling in and out of a fifth-grader's school bench, without anyone providing him with suitable seating. Another comic high spot has Jack diving between his parents in bed as they were about to have sex, and demanding successfully to spend the night in their midst. But even the real children in the film appear to have been chosen for their gracelessness.

The lachrymose ending, in which Jack, an aged valedictorian, urges his youthful classmates to seize the day and not judge the value of a life by its duration, while his proud parents clutch a normal little daughter to their bosoms, suggests to me that the film's not-so-secret agenda is as a sop to the age of AIDS, a very real illness whose symptoms bear a crude resemblance to Jack's malady. If so, the film is even more unsavory, rather like its gimcrack and attitudinizing score by Michael Kamen.

There are two redeeming features: the enchanting Diane Lane as Jack's mother, and the no less enchanting Jennifer Lopez as a sympathetic teacher. But though these lovely ladies and fine actresses salvage much, it is nowhere near enough.