Every night an audience of several hundred aims its gaze at Fiona Shaw, who has the title role in the Broadway production of Medea by Euripedes. She portrays a woman who murders her children as revenge against Jason, her unfaithful husband. Shaw, the New York Times theater critic Ben Brantley and the play’s director, Deborah Warner, talk about the spectacular and the tragic in Medea. Produced by Leital Molad.