Two literary legends, writer Robert Caro and his longtime editor, Robert Gottlieb, have worked together to create some of the greatest non-fiction books in history. Now 86, Caro is determined to complete the final volume of his masterwork, "The Years of Lyndon Johnson"; Gottlieb, 91, wants to edit it. With humor and insight, this unique double portrait reveals the work habits, peculiarities, and professional joys of these two ferocious intellects as they attempt to finish the final masterstroke in their life's work.