The Georgetown Classical Theatre, opening a summer season at ASTA Theatre, has placed Brecht's "The Good Woman of Setzuan" in Saigon of the late '60s. The shoe fits, as far as it goes, though it doesn't begin to cover the whole body of Brecht's play. However, the GCt seems aware of the limitations of its Saigon hook and has also taken care to keep Brecht alive and well. This is a thoughtful and sometimes striking production.

Both Brecht's Setzuan and the Americanized Saigon were societies cut off from the communal ties that once bound. Both were awash in desperation and greed. In both, the GCT suggests, a good woman was hard to find and those who tried to be good found it hard.

Harry Sumrall's score is the most effective embodiment of the Saigon connection. Brecht's lyrics have been adapted to vaguely orientalized American pop music, which slashes into the texture of the play with just the sort of alienating effect Brecht intended. The music demands that we drop any naturalistic dreams aroused by the play and think about what Brecht is saying.

In other respects, however, the topical references are slight and superficial, and the more cosmic overtones of Brecht are allowed to breathe.

They breathe very deeply in the performance of Karen Bayly as the good woman, Shen Te, and her pragmatic alter ego. Shui Ta, who periodically resumes Shen Te from her benevolent impulses. Bayly zigzags between the two roles with complete credibility and, at the end, wrenching pain.

Her performances is matched by Ken Kelleher's as Wang, the lowly water seller. He too is transformed here - into a magnetic rock star for two of the musical interludes. (However, the lyrics of his "Song of the Eighth Elephant" are difficult to understand.)

The rest of the cast is not uniformly up to the standards of Bayly and Kelleher. Director C. A. Duncombe's imagination has produced some fine moments, but his work could use more economy. And as resident designer for the GCT, he should do something about the sets. They're too complicated for such a small space, and too much time is wasted serving their needs. This "Good Woman" is strong enough and stirring enough without their representational detail.

GCT's summer season is devoted to strong women facing complex moral dilemmas. "Good Woman" plays through July 15 andwill be followed by Alberto Moravia's "Beatrice Cenci" and Shakespeare's "Measure for Measure."