DONT LET THEM kid you.

Movies about decadence are as American as apple pie. It is no wonder that Cabaret has transformed Sally Bowles, the wayward English schoolgirl of Christopher Isherwood's Berlin Stories, into an offbeat American princess, and that America, in loving recognition, has responded by placing Liza Minelli, the reigning Sally Bowles, on the covers of both its major news magazines.

Cabaret's treatment of decadence, however, signals only one major change in the Hollywood mentality. Where the movies once had to turn to towns like Sodom and Gomorrah for titillating and moralistic examples of vice unfettered, they now need go no further than the early days of the Third Reich. Movies as different as Stanley Kramer's Ship of Fools. Lucino Visconti's The Damned. Hal Prince's Something for Everyone and Bertolluci's The Conformist have begun to pick and prod the corpses of Nazi Germany and Fascist Italy in search of moral parallels to our own, none-too-healthy times. (And, though it's true Visconti and Bertolluci can hardly be dismissed as Hollywood hacks, the very fact that their films, once made, were eagerly distributed by major American studios, shows that Hollywood's new corporate moguls liked what they saw.)

Hollywood, though, is not entirely to blame: look no further than your own local campus, where, for some time now, the kids have called their professors Fascists and the professors have spurned their students as Nazis, and you have some idea of how compelling the Nazi parallel is to Americans suffering their own special kinds of sturm and drang. America is no longer sure of her own moral rectitude, and Nazi Germany offers a convenient--and haunting--example of how wrong things can go.

Now, the last thing you might expect to find amid such hypercharged emotionalism is an affecting musical. And Cabaret, in dealing with the beginning of the Nazi end, takes a good many chances. Its hopes is that decadence can be at once entertaining and instructive, and that its historical milieu can provide a poignant contrast to the lives of its characters. The danger is that the decadence will shine forth as either bogus or overwhelming, and that the historical setting will overshadow the characters poised before it. Cabaret gambles on the trade and, I fear, it loses. But though it fails to execute the move completely it's still one of the deftest entertainments around.

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CABARET WAS a watershed of a musical and it is even more of an achievement as a film. Produced by Hal Prince, directed by Joe Masteroff, with music and lyrics by John Kander and Fred Ebb. Cabaret appeared on Broadway in 1966 to deliver a telling blow to the old-fashioned Broadway musical where songs served merely as dialogue and the songs cue was king. Ever since Oklahoma' had hit the scene in the forties, musicals were presumed to be merely souped up dramas. Lyrics had to advance the plot and dances were expected to serve some dramatic function. Cabaret was one of the few musicals of the middle sixties to say that needn't be so. Although Cabaret did retain many vestiges of the traditional musical--it had a plot all right and its characters still sang their thoughts to each other whenever that plot hit a crucial junction--it also introduced seemingly non-integrated throwaway numbers that commented on the plot rather than advance it. It all looked innocent enough--since Sally Bowles, the play's heroine, sings in a sleazy Berlin nightclub, the Kit Kat Klub, it was only natural that the musical would utilize some of the numbers she would have sung on the job. The effect, however, proved far more insidious.

The Kit Kat Klub--underneath its rouged and mascaraed exterior--possesses a knowing intelligence in the character of its Master of Ceremonies--as played by Joel Grey, a wicked little man who as readily agrees to pinch-hit as a chorus girl in drag as he assumes the role of death's subaltern on earth, doing both with a manic enthusiasm that belongs only to the dying and damned. With Grey's M.C. on hand, the conventional half of Cabaret was never even in the running.

Cabaret was a musical with both intelligence and style and what more could a body want. Its importance was made all the clearer when it spawned such other Hal Prince efforts as Zorba, where the commentator's role was taken over by the musical's entire ensemble: Company, which the cane-stomping choreography of a number like Cabaret's "Wilkommen" reappears in "Side by Side" and "What Would We Do Without You?"; and Follies, in whose case Cabaret's final ghost-ridden moments give way to a whole production hung halfway between the present and the past.

Bob Fosse--in bringing Cabaret to the screen--has done well to sacrifice none of these innovations. The core of his film is still the cabaret numbers themselves, played out on a cramped, cluttered stage given depth and dimension only by Geoffrey Unsworth's cleverly stark lighting effects. Throughout, Fosse's own particular wit as a choreographer of decadence--his "Rich Man's Frug" was one of the best things in his earlier staging of Sweet Charity--serves to summon up a wealth of period references--the tinkly, jarring music of Kurt Weill, the angular, fantastic interiors of Dr. Caligari, the smoky torch songs of Blue Angel, and the bloated Bacchanites of George Grosz. In fact, his effects are occasionally so persuasive as to be claustrophobic--particularly when you add the excess of close-ups Fosse uses to tell his story.

However, Fosse does not do so well in capturing the essence of Fraulein Sally Bowles. As the unsinkable Sally, Liza Minelli is asked to play an American girl abroad, a bit of a nightclub performer and a bit more of a whore. Sporting green fingernails ("Divine Decadence," she purrs to guests in explanation), downing Prairie Cocktails (raw eggs, whisky and worchestershire designed to get rid of the "worst hangovers") and always looking for that one lay which will bring her fortune and fame. Sally is a desperate character whose high spirits are the only assurance she has that she can keep from being a loser. Given half a chance, I suspect that Miss Minnelli might have had the range for such a part--but that half a chance isn't given her. Instead she is forced into another replay of the kooky Pookie Adams she played in The Sterile Cuckoo--a spirited, imaginative unhappy little girl who's never recovered from the debilitating effects of an unloving father. Only in her musical numbers and in one comic scene--a teaparty meeting between the theatrically slutty Miss Minnelli and a proper Jewish girl (Marisa Berenson)--is she able to project a kind of adult authority.

It's all very sad. One suspects that the chief reason Miss Minnelli is asked, and consents, to play her role is that she lacks conventional beauty. On screen, she is continually apologizing for her appearance, asking "Doesn't my body drive you wild?" in self-deprecating good spirits, and mugging incessantly as if she thinks she is any the more attractive in a state of perpetual motion. Miss Minnelli is simply another victim of a double standard that remains anachronistically true of today's movies: while actors who aren't conventionally handsome--Alan Arkin. Dustin Hoffman. Eliot Gould--are permitted to admit to a certain degree of sexual attractiveness, actresses who aren't conventionally beautiful--Minnelli. Barbra Streisand--must play it strictly for laughs. (And meanwhile, the irony of it is that the "conventionally" attractive actor or actress is no longer in particular demand.)

Michael York is the type of actor who has to overcome his conventional good looks before he can begin to make an actor's claims on your attention. As Brian Roberts, the Isherwood stand-in, a Cambridge graduate student who seems constantly in danger of prematurely becoming an English Don. York offers a soft-spoken, understated performance that appears deceptively serene in its controlled use of nuance and shading. In contrast, Joel Grey's shtick has picked up an added touch of the grotesque along the way. There are moments when it loses some of its original spontaneity--Grey now reads his punch lines as if he is a Cassandra who Knows, but isn't telling--but the overall effect remains seductive and riveting.

It is really Fosse's supple use of editing that holds the film together though. Its best moment, in my mind, occurs as Minnelli and York kiss and begin to make love while the camera threatens to fade into the phoney discreteness of a rain-soaked window. Suddenly, the rain becomes the smokey white light of the cabaret and Miss Minnelli's head returns to view as she begins to sing "Maybe This Time," a lovely Judy Garland type song that meshes perfectly with the previous scene. In achieving a balanced counterpoint between movie "reality" and movie "artifice," Cabaret saves itself from the cloying theatricality that mars most movie musicals.

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