THE LAST WAVE -- Dupont Circle.

The best scene in "The Last Wave" shows a blond Australian couple oozing nervous equality as they welcome two fierce, silent Aborigines to their glass-and-chrome dinner table. The wife tries charmingly to draw out a magically possessed elder by mentioning modestly that she, too, is an artist.

Or perhaps it's the scene in which Richard Chamberlain, taking on a tribal murder case as part of his legal-aid charity work, explains to a sullen lineup of suspects that they will have to be patient with him because "my field is corporate taxation."

These are wonderful, if inadvertent, satiric portraits of liberal gentility. But in attempting to be an occult film, a disaster film and a racial-guilt film, all at once, "The Last Wave" neglects its potential for being a memorable social-comic film.This is a shame, not only because of these tantalizing moments but because the film lacks a cohesive viewpoint. The horror is not strong enough to do it, but comedy could have been devastating.

For his intentional themes, Peter Weir has assembled a Biblical flood and a people who are both oppressed and supernatural, and let them loose on Chamberlain as the epitomy of effete, European-descended civilization, complete with tennis court. Although the wife is a fourth-generation Australian who spends her evenings reading coffeetable books on the Aborigines, she has apparently not checked out her husband's bloodline enough to avoid bringing trouble into the family.

Weir's point must have been to invest the Aborigines with a culturally rich dignity and the whites with a corresponding amount of guilt.

But the celebration of "natives" for a kind of rhythm of the soul is patronizing, and the awkward way in which the whites try too hard to do the right thing makes them vulnerable as well as funny. Vulnerability is an essential quality in an occult film, but it's ruinous in a story of racial oppression. You can't hold these people responsible for anything requiring as much strength as subjugating a continent.

They are even emotionally too flimsy to be proper victims for a natural-disaster film. Early in the movie, as a portent, the lawyer discovers water pouring ominously down his carpeted staircase. It turns out that one of the couple's angelic-looking little daughters forgot to turn off the bathtub faucet, an explanation so reasonable that it should bar the incident from claiming association with the cosmic Last Wave of the title.

But an ordinary leaky ceiling seems quite as much trouble as these people can handle, or rather more. Demons, apocalypses and historical racism they don't need.