Several years ago on a whim, Culleton requested James Joyce's FBI file. Hoover had Joyce under surveillance as a suspected Communist, and the chain of cross-references that Culleton followed from Joyce's file lead her to obscenity trials and, less obviously, to a plot to assassinate Irish labour leader James Larkin. Hoover devoted a great deal of energy to keeping watch on intellectuals and considered literature to be dangerous on a number of levels...