Undated (AP) _ Max Baron is a compulsive, Jewish yuppie whose childhood sweetheart and wife died in a car crash. Nora Baker is a vodka-swilling, coarse, lapsed Catholic who sells 49-cent hamburgers and whose teen-age son died from alcohol and drug abuse.

He's 27; she's 43.

He's a neat freak; she's a slob.

He likes Verdi; she likes the Oak Ridge Boys.

He reads Proust; she watches ''Wheel of Fortune.''

About the only thing they have in common is passion ... and lust.

Their opposite worlds collide in Luis Mandoki's ''White Palace,'' a smart- talking sexy romance, with the deliciously sensual Susan Sarandon giving yet another earthy, close-to-the-heart performance as the brassy Nora.

The older woman-younger man syndrome has been treated in dozens of movies over the years, such as ''Mrs. Skeffington,'' ''The Roman Spring of Mrs. Stone,'' ''Harold and Maude,'' ''Class'' and ''A Tiger's Tale.''

But in ''White Palace,'' based on the novel by Glenn Savan, the age issue takes a back seat to class differences.

The serious problems and disagreements Max (James Spader) and Nora encounter in their relationship have nothing to do with her wrinkles or his youthful allure. Rather, they stem from his reluctance to have his friends and family see her in her waitress uniform or know that she lives in ''Dogtown'' - the dirty side of the tracks in St. Louis, Mo. - and from her defensiveness over who and what she is.

They meet one night when Max returns to the cheap hamburger joint where Nora works to complain that six of the 50 burgers he purchased for a bachelor party were missing. They exchange sharp words.

Later, after seeing a picture of his dead wife at the party, Max, in a flood of emotions, leaves and stops at a dingy tavern. Big, but very big coincidence (how else can we get the movie rolling?): Nora is sitting at the bar, four sheets to the wind.

Nora tries to seduce him and finally convinces him that he should drive her home and get some coffee so he can sober up. They get to her place. No coffee. He passes out, only to be revived to orgasm by a ravenous Nora.

''White Palace'' gets off to a steamy start with lusty lovemaking, and unravels a gutsy portrait of gutsy lovers.

The worldly Nora lets Max into her world, although she hides the circumstances of her son's death. They rendezvous only at her dirty home, and she is furious when he gives her his first present - a Dustbuster.

He meets her older sister, Judy (Eileen Brennan), who dabbles in the occult and reads palms.

Finally, he invites her to his sterile and expensive apartment. She forces him to play back his phone messages and embarrasses him into accepting an invitation to Thanksgiving dinner at the Horowitzes, Max's close friends.

Max's friends and family are educated and affluent, but are just as lacking in good taste, class and breeding as Nora. Nora's attire is dime store polyester; the women at the dinner party paid hundreds for tasteless and gaudy ensembles. Nora is confrontational and defensive - she describes her work as ''food preparation''; Max's friends are not very gracious and do nothing to make her feel welcome and at ease.

After rudely telling off Sol Horowitz (Steven Hill), Nora leaves. Max follows. But Nora feels theirs is a relationship that could never work. She packs and leaves town, instructing Max not to follow. (Don't worry. There's a happy ending here, with a sexy conclusion.)

Spader and Sarandon are a good, romantic mix, and spar well with the snappy dialogue from Ted Tally's and Alvin Sargent's screenplay. But ''White Palace'' is Sarandon's movie. She dominates in every scene, her tough professionalism and sensitive timing illuminating every frame.

Spader is spare with Max, as he should be; Max is a reticent kind of guy. But he often holds back too much and is too often tentativein his approach. An example, the bar scene: Sarandon is a believable drunk; Spader appears as an actor acting like a drunk.

Mandoki (''Gaby - A True Story'') likes to linger on the moment and captures nice pieces of business. He draws a humanity from his characters, a universality.

''White Palace'' is more than a romance or a bedroom romp or human comedy. It is a lesson in judgments and values, and a glimpse at emotional roulette.

The Mirage-Double Play production was produced by Mark Rosenberg, Amy Robinson and Griffin Dunne with Sydney Pollack as executive producer. The Universal Pictures release is rated R.

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Motion Picture Association of America rating definitions:

G - General audiences. All ages admitted.

PG - Parental guidance suggested. Some material may not be suitable for children.

PG-13 - Special parental guidance strongly suggested for children under 13. Some material may be inappropriate for young children.

R - Restricted. Under 17 requires accompanying parent or adult guardian.

NC-17 - No one under 17 admitted.