Drama is not usually found on the dinner theater menu, but the Manassas, Va., Hayloft makes one of its occasional exceptions with "Cat on a Hot Tin Roof." To my surprise, Terry Kester's production of the Tennessee Williams scorcher is a capable one, thanks especially to the four leads.

This is the story about Big Daddy, glorying in "28,000 acres of th' richest land this side of the Valley Nile." Award of death, he wants his estate to go to his preferred younger son, Brick, rather than to the elder Gopper, whose grasping wife, Mae, has spawned a half-dozen children, while Brick's wife, "Maggie the Cat," has produced none.

The deterrent factor is the cloud between Brick and Maggie resulting from the suicide of Brick's football pal, Skipper. Was the relationship pure friendship, as Brick insists, or was it homosexual, as the playwright, through Maggie, suggests?

Time alters dramatic atmosphere. In the 23 years since "Cat's" appearance, homosexuality has become more openly discussed while Williams himself has stretched in both directions. He remains opaque in his plays, joltingly factual in his personal memoirs. In "Cat" time and drugstore psychology have made Brick's relationship to the dead Skipper far clearer but just as equivocal.

In his staging, director Kester has used more of the Broadway-Elia Kazan version than the original, both of which Williams printed in the published version. Big Daddy's coarse anecdotes about Moroccan children and an aroused elephant are excised with no diminution to the play. And, as here staged, the relationship between strong Maggie and weak Brick is clearly, effectively defined.

The best of the play lies in the Act II verbal jousting between Brick and Big Daddy, that character so commanding that Kazan pushed Williams into including him in the Act III revision. Gerald Graham Brown and J. Robert Dietz do this superb scene splendidly. Initially I had thought Brown's Brick affected but by the end he has built Brick with strong consistency though his Ole Miss, accent does sound too contrived.

Created by Burl Ives, Big Daddy is a superb role. Familiar actor that he is, I didn't think Dietz would have a Big Daddy in him, but he does indeed, the best of the many performances I've seen him give. The Maggie of Christi Warnick manages to indicate intelligent awareness without sacrificing our sympathy. Finally, Jean Schertles, another area veteran, is splendid as Big Mama, the best I've seen since Mildred Dunnock's original.