The play doesn't shift radically from one cast list to the next to the next. Mr. Sullivan's confident production doesn't deny melodrama, but it prefers psychological and social detail over Southern gothic fripperies. (Scott Pask's fraying, elegant set and Jane Greenwood's shrewd costumes, with ruffles for Birdie and a sleeker silhouette for Regina, also reflect this emphasis.) It asks both actresses to make the roles more than villain and victim, which the play allows. You might wish that Hellman had written the faithful retainer parts with greater breadth, but Charles Turner and particularly Caroline Stefanie Clay play them with nuance.