Eugene O'Neill's updated version of the Oresteia. In New England, after the American Civil War, a war-weary Agamemnon, Brigadier General Ezra Mannon (Raymond Massey) comes home to his unhappy wife Christine (Katina Paxinou) and loving daughter Lavinia (Rosalind Russell). But Lavinia's ex-suitor, Adam Brant (Leo Genn), has become Christine's lover, and together Adam and Christine plot to poison Ezra. When they succeed, Lavinia turns to her brother Orin (Sir Michael Redgrave) to help bring the lovers to justice, but when they succeed, Orin goes mad and his suicide note may come between Lavinia and her new suitor, Peter Niles (Kirk Douglas).