ONE OF BRITAINS most gifted young writers has decided to be cute about Hitler. Beryl Bainbridge's latest novel-the fictional recreation of a trip that young Adolf may have taken to Liverpool in 1912-could be part of the new phenomenon of "post scandalism." We have been inured to shock, in all media, by a sensationalism that verges on rebarbarization: chiefs of state sodomize death row inmates (Robert Coover); 14-year-olds seduce their moms (Louis Malle); cannibalism returns (Jean-Luc Godard); parents watch their children being killed in car accidents (John Irving). Having so vastly dehumanized the human, could we now be seeking a new brand of frissons by humanizing the inhumans? See the beautifully-written, titillating little novel about five months in the early life of the further, Bainbridge's seventh work of fiction in seven years.

It is an accepted fact that Adolf Hitler had a half-brother, Alois, who lived in Liverpool in the '20s and supported himself as a waiter and part-time salesman of razor blades. Bainbridge has been led to believe by less reliable sources (she cites Robert Payne's biography) that an entry in dairy of Alois' wife registers young Adolf's arrival in England at the time he was attempting to evade military service in Austria.

Bainbridge sets her fantasy in the seedy boarding house which Adolf shares for five months with a cast of dropouts almost as destitute as himself: His dominating, sadistic half-brother; a philosophizing, fiddle-playing Jewish landlord, Mr. Meyer, who dabbles in indistinct semi-revolutionary activities; and Alois' timied, puttering wife Bridget, who is prone to much domestic worrying (" 'I wish I hadn't done mutton,' " she reflects as she awaits her relative's arrival from Vienna.)

Young Adolf himself is depicted as a self-pitying, parasitical, sniveling waif psychotically convinced that total strangers are pursuing him. His arrival is welcome by no one (he does not even have the proper immigration papers), and he spends whole days asleep on his relatives' sofa, abjectly anxious to be loved while being quite devoid of any trait that could endear him to anyone. Bainbridge accounts very craftily for young Adolf's more famous later characteristics: He is a loner incapable of friendship, who thrills to Wagner's music. He combs his hair over one side of his forehead to hide a cut on his brow. He occasionally rants about "impure blood" and the rotten core of Europe. And at the novel's end, when he takes a turn at transvestitism and puts on a skirt to evade police hunting illegal aliens, he resolves to grow a mustache in order to never be mistaken for a woman again.

What Bainbridge banks on in this work (she admits it in her epilogue) is a brand of Chaplinesque comic. "I intended, if anything, to make Adolf as absurd a figure in words as Charlie Chaplin had made him on film." She is determined to keep her anti-hero "a cardboard figure." And she limns several Chaplinesque moments. Here is Adolf in the Liverpool hotel in which he works as a bellhop, imagining he is pursued by a bearded oppressor whom he fantasizes about throughout the novel. "Running ful tilt along the corridor . . . skidding around the curve of the staircase, he leapt into the foyer and hurled himself into the revolving doors . . . He took the wall of the cab stand in his stride and landed on his feet in the street below." But Bainbridge does not begin to achieve Chaplin's magic beyond such slapstick cinematic tricks of high speed motion and exaggerated gesture. Ih The Great Dictator , Chaplin constantly kept us balanced between amusement and horror, involved the terror or history in the suspension of our disbelief. Bainbridge wants only "cardboard," and cardboard is all she gets. The mystery of evil which made young Adolf grow into a demonie force, which differnetiated him from thousands of other frustrated rejects with delusions of grandeur, is never alluded to. Adolf remains as two-dimensional, gruel-thin and tiresome as Bainbridge's other male characters, for as in many current women's novels, alas, only the women (Bridget in particular) seem to come alive.

I occasionally found Young Adolf pleasurable on strictly formalist grounds. Bainbridge is a brilliant technician. However devoid she is of psychological texture, her ear for British dialogue is devastating; her gifts for physical description are formidable. "Meyer's apartment had a grandeur that might have been oppressive but for the fact that each time the door was opened or closed quantities of plaster fell from the ceiling and clung like snow to every available surface. The furniture, old and dark, monumental in size, was liberally sprinkled with flakes of white, as were the windowsills. The effect was festive."

The novel is occasionally redeemed by a glacially ironic, parochial British wit which merges nicely with the historic detail. Bridget decides to sew some clothing for her tattered brother-in-law and finds nothing but a piece of brown linen in her closet. "'Brown,' Bridget said dubiously. 'It's an odd color for a shirt.'"

"'Such a strong-willed young man.'" Meyer says later. "'It is a pity that he won't amount to anything.'"

"'Ah,'" Birdget reflects when to everyone's relief Adolf returns to Austria, "'and he's never even been to New Brighton.'"

It is upon such delectably clever quips that the novel's gallows humor hangs. I remained quite perplexed, throughout, by the considerable aesthetic and moral problems of producing a charming novel about one of the two or three greatest monsters of human history. Within this fashionsbel new theme of fascinating fascism, Bainbridge's Young Adolf totally pales before the hilarious "Springtime for Hitler" sequence in Mei Brooks' The Producers , which always remains on a rigorously surreal, abrasive level of black humor, and is never domesticated into Bainbridge's lapidary, kinky elegance. In our strange new need to dehumanize the human-which may become one of the sensationalisms of the '80s-there is no end to trivializing the components of the Holocaust. Making evil banal is dangerous enough. Being cute about it is outrageous-which is perhaps just what Bainbridge wants to be.

"When people get accustomed to horrors," Boris Pasternak wrote, "these form the foundation of good style. Shall we ever understand how the guillotine could be temporarily made the decoration for a lady's brooch?" CAPTION: Picture, Woodcut of Hitler, by Jack Crawford (1934)