BERNARDO BERTOLUCCI doesn't seem to take things halfway. If his Last Tango in Paris contained some of the most graphic sex that had ever been offered to general audiences in 1972, 1900 is one of the most concerted efforts ever to put the class struggle on the screen. By the end of the four-hour film, Bertolucci has completely exhausted his audience, as much emotionally as physically.

1900 didn't have to be so long, or so intense. Had Bertolucci felt more kindly toward his audiences, he could have made his tale a simple epic--45 years of conflict between landlords and peasants in northern Italy, living out a history most of us already know. He could have shown us the breakdown of the traditional patronage system under the influence of industrialization, the rise of peasant leagues, the landlords' reaction and the spread of fascism without involving us so totally; or he could have shown us the characters' interaction without making such a detailed effort to place their lives in a social and political context.

This is the story of the relationship between two boys born in 1900, and the story of the relationship between their families--one of which owns the land that the other tills. It is immense, overflowing with color and detail; unfortunately, it comes close to being indigestible.

If 1900 is hard to swallow, it is partly because the epic is flecked with moments of perverse brutality, a kind of sensuous enjoyment of the grotesque. At the film's end, scenes that made the audience shudder aloud in the opening few minutes are repeated; and now they seem commonplace, even acceptable, for the film had had far more brutal moments. At times, Bertolucci's love for vivid detail and for visual lushness results in scenes of great beauty--a bride galloping on a white horse through the mist and poplar trees, a small boy playing in the river, a group of peasant women resisting the landlords against a red sunset. But just as often, Bertolucci also gives us scenes guaranteed to horrify: a man sacing off his ear, a boy's head smashed against a wall. If he goes to extremes in length and content, Bertolucci goes to even greater ones in purely physical terms.

Even if these scenes didn't wrench us out of the normal world, perhaps, the story would, for it is often as difficult to fathom as the wanton brutality. Robert De Niro and Gerard Depardieu, as landlord and peasant, are bound together, unable to abandon either their friendship or their class positions. The two were boys together: DeNiro always following and admiring the peasant Depardieu; but their friendship was always flawed because, as Depardieu says, "I caught the frogs your family ate."

From the first, their lives are complicated by the other characters. Their families make demands on them as children, and when they grow up there are the peasants who look to Depardieu, a fierce socialist, for leadership, and the landlords and fascists who look to De Niro to support their efforts to subdue the peasants. There are women, a dedicated socialist and a half made dilettante. And of course, there are the historical forces, requiring De Niro to choose between his socialism and his position as a landlord. 1900 unfolds on many levels; it is hard to keep up with all of them at once.

The film's plot isn't helped any by the loss of two hours from the original six-hour film. The version now showing here leaves a great many gaps, and it's impossible to tell whether Bertolucci meant to leave details vague or whether they were cut for the U.S. market. It is never clear, for instance, why De Niro's insane cousin loves him, or why she and her fascist lover become so perversely destructive; nor is it completely clear why De Niro stands by as the fascists take control of his town.

By the end, however, clarity may not matter, for the film leaves the real world behind and enters the realm of allegory. When the fascists are driven out of Rome, the peasants turn on the fascists of their own town, and then it is the padrone's turn. Passive as ever, De Niro stands before a people's tribunal--under a huge red flag that is miraculously unharmed by the bayonets that hold it up. But if De Niro retained his love for his peasant friend throughout the fascist period, Depardieu cannot overcome his ties to De Niro and he does not permit the tribunal to reach its natural conclusion.

This, Bertolucci seems to suggest, is the reason the class struggle remains unresolved: personal ties obscure class warfare, ideology notwithstanding; it is hard to kill people one has always known. As young men, De Niro and Depardieu fought each other to prove their courage; as old men, they will fight, but the struggle has become oddly depersonalized, the inevitable outcome of the existence of a class system.

It is unfortunate that Bertolucci chose to portray unresolveable tension; whether or not his message is valid, it does not lend itself easily to a heavyhanded treatment. The main conflict in 1900 is the love these two men bear for each other, across ideological and social grounds; and the main question we are left with is why they bear it. De Niro and Depardieu are both fine actors, and play their roles well, so the fault lies elsewhere--probably with their director. In his effort to give 1900 an epic vastness, it seems, Bertolucci lost sight of the smaller things, the individuals around whom the epic apparently revolves.

All of this does not make 1900 a complete failure, by any means. Few directors would take on such a grandiose 'ask, and few could come so close to achieving success. From the film's early scenes of life in the Italian countryside at the turn of the century, 1900 draws in the audience, keeps it involved, and only lets it go in the last moments. The ending--which drifts off from the allegorical to the surreal--is completely unsatisfactory, but then, 1900 is too rich to take in all at once. A last-ditch effort to make the film into a bite-sized chunk couldn't have worked. This is, perhaps, a disaster, but one of magnificent--and unforgettable--proportions.