Kathleen Dowdey, a young documentary filmmaker from Washington, aspires to a fresh synthesis of cultural anthropology and political advocacy in her feature "A Celtic Trilogy," which begins a brief engagement today at the Inner Circle.

Shot principally in Ireland, South Wales, Brittany, Belfast and Edinburgh, the movie attempts to weave strands of travelogue, historical background, folk art, dramatic recitation and interviews into a celebration of Celtic cultural traditions. That celebration in turn provides a rationale for increased political influence and even autonomy among people committed to preserving the traditions.

It's not necessary to share Dowdey's strong sentimental attachment to a Celtic heritage or her rosy view of separatist politics to find her film informative and provocative. It helps , but it isn't absolutely necessary. iFor example, I find it hard to become enthusiastic over Irish actress Siobhan McKenna declaiming rhapsodically about Brigit, Diedre, Iseult and other folk heroines while posed beside a waterfall, or to become excited over signs of bilingualism making headway in Wales and Brittany.

But even to a skeptic, Dowdey's obvious sincerity and earnest, inquisitive approach exert a disarming appeal. She seems to be seeking confirmation of beliefs that remain unresolved, or at least open to debate, in her own mind.

The interview sequences lack contradictory voices, but suggest an attentive, thoughtful observer. Those interviewed include: a Druidic monk in Brittany; an Irish Catholic Priest who organized a fishing and canning cooperative in a Donegal village; the president of the Welsh Nationalist Party; a Breton sculptor; and an Ulster Protestant, the remarkably sympathetic and eloquent Andy McCann, who hopes for reconciliation through political independence, theoretically minimizing dominance from either London or Dublin.

The straightforward quality of these interviews tends to make the dubious rhetorical sequences stick out like a handful of swollen thumbs. The most extended and outrageous example superimposes McKenna's narration of atrocity stories about Oliver Cromwell over shots of a stockyard in County Kildare. The equation of Cattle herds with Cromwell's victims is flagrantly counterfeit. Given a less inflammatory narration, the same footage would merely document a thriving native industry that the filmmaker probably considers praiseworthy.

The title, stemming from a rather arbitrary division of the footage into three chapters, is a bit prompous. "A Celtic Journey" might be preferable. This happens to be one of the few movies I've had the opportunity of seeing in a rough-cut form. At that time Dowdey appeared to face a discouraging editing task, because the footage rambled ponderously for better than three hours. She also seemed unwisely deferential to McKenna, whose long oratorical appearances constituted an arty ball-and-chain. Whenever McKenna was allowed to dominate the proceedings, the film became pictorially inert and verbally monotonous.

Dowdey has succeeded in refining a nearly excruciating heap of footage to a fairly crisp and suggestive hour and a half. The editing hasn't sacrificed a single crucial participant or issue. Indeed, the conception is enhanced by Dowdey's ability to discover and illuminate her theme in half the time she originally required.

Although 30 seconds of exposure to McKenna's melodious bombast lasts an eternity as far as I'm concerned, even this imposing obstacle has been reduced to the manageable proportion of a quaintly echoing affectation.