A comprehensive and well-researched account of J. Edgar Hoover's life. Theoharis has probably done more than anyone to piece together (through interviews, FOIA and other research) Hoover's multi-decade campaign to make the FBI the most powerful agency in the federal government. The author makes no secret of his dislike for Hoover, and sometimes that sentiment can bleed into the analysis a little too much. Other biographies are a bit more even-handed. Also, the book shows its age at points when Theoharis injects some kind of dated and crazy-sounding psychological theories into his profile of Hoover. Still, he is a good historian and his research set the standard for other writers on the subject.