Lacking Callas's elegance, the estimable Tyne Daly nonetheless controls the stage and the audience with command, and lends shading to the writing wherever she can; less successful are the three actors playing her students, guided with a heavy hand by Stephen Wadsworth. The pedagogical sequences, at least, have a patina of high culture, unlike the pair of vulgar, melodramatic flashbacks about Callas's doomed affair with Aristotle Onassis that form the climaxes of both acts. 'This is a master class, not a psychiatrist's office,' she announces early on-to no avail. Stripping La Divina of both mastery and class, McNally shrinks her with a vengeance.