Book excerpt: Based on revealing letters and other documents from archives, Hemingway and His Conspirators has the dramatic personae of a Hollywood production--with a cast starring not only Hemingway and Perkins, but F. Scott Fitzgerald, Helen Hayes, David O. Selznick, and Gary Cooper. Set in an endlessly fascinating age, the 1920s. It tells a backstage story of the tangle of literature, publishing, and motion pictures in the formative years of a time when the possibilities of a new mass audience challenged and changed culture and literature forever.