`Betrayed' focuses on neofascism. Costa-Gavras directs well-intentioned movie

There's nothing more repugnant in the United States today than the small but disturbing number of white supremacists and other neofascists. Their activities and the social implications of this phenomenon seem a natural and urgent subject for serious filmmakers to explore. ``Betrayed'' is the first American movie to take a probing look at current neofascism. The cast features Debra Winger and Tom Berenger, two of Hollywood's most popular stars. The picture was directed by Constatin Costa-Gavras, who has a long record of politically conscious films, including ``Z'' and ``Missing.''

The film is unquestionably sincere in its attempt to deal with a difficult and potentially controversial topic. But what should have been a searing political thriller turns out to be a sadly unconvincing melodrama.

Miss Winger plays an undercover FBI agent. Her boss, played by John Heard, asks her to infiltrate a farm community in the Midwest where a neofascist group has been linked to a murder. One of the first people she meets is Tom Berenger, as a handsome widower with a couple of children.

He's such a wholesome family man that she can't believe he's involved with fascism. In fact, she can't believe there is any fascism in this quiet town. Before she knows it, she's deliriously in love with her new friend - only to find, after she's moved in with him, that he's up to his neck in hatred and violence.

There's nothing wrong with this story idea. In fact, ``Betrayed'' promises to be a sizzling movie when Winger starts realizing the truth about her lover, and finds herself drawn into his horrible world.

The trouble with ``Betrayed'' is that it never gets one inch below the surface of its plot. It suggests that much of Middle America - all linked up in a secret computer network - is tainted by bigotry of the most horrible kind. But after making this charge, it fails to give any kind of explanation, except for simplistic remarks about how tough things have been for farmers lately.

The plot gets more hokey as it goes along: It's ludicrous to see a big assassination attempt become a sort of afterthought while the characters get worked up about their relationship problems. Then, when the FBI finally makes its big move, we don't see it; we hear about it, as if this were a play instead of a movie. Afterward comes a sort of coda, when the Winger character hits the road to ponder the events in a sequence that's so shallow and cursory it would be embarrassing even it weren't so old-fashioned.

``Betrayed'' means well, and its makers earn a modicum of praise for having the courage to tackle a difficult subject. Unfortunately, that subject is still waiting for a movie that will do it justice.

The film's rating is R, reflecting some violence and pointedly foul language.