Author-screenwriter John Gregory Dunne died of a heart attack on Tuesday, just as he and wife Joan Didion were sitting down to dinner. He was 71. Beloved members of Manhattan's literary scene, Dunne and Didion co-wrote screenplays for films like A Star Is Born (the Barbra Streisand remake) and True Confessions, co-starring Robert DeNiro and Robert Duvall. Dunne was also the brother of crime writer Dominick Dunne, who hosts Court TV's Power, Privilege and Justice.