The material, carefully chosen to show Callas at her best and most versatile, includes "Casta Diva" from Bellini's Norma (a Callas specialty), the haunting "Miserere" scene from Verdi's Il trovatore, and the mischievous "Una voce poco fa" from Rossini's Barber of Seville, a fine series of stylistic contrasts in which the essential point is not pure tonal beauty but characterization and subtle expressive nuances. Others have made this music sound prettier; nobody has presented it with more impact.

But the climax of this program is its second half, a staged performance of Act II of Puccini's Tosca. This is a study in police brutality, sexual harassment, and sheer violence, psychological and physical, that has some of opera's most extreme moments--including the great aria "Vissi d'arte," the murder of the villain Scarpia, and the contemptuous dismissal flung at his corpse--"and all Rome trembled before him!" In this segment, Callas goes mano a mano with Tito Gobbi, her only equal as a singing actor during her career. They savor this material in a virtuoso performance. --Joe McLellan