Book excerpt: Between 1933 and 1939, the FBI pursued an aggressive, highly publicized nationwide campaign against a succession of Depression era "public enemies," including John Dillinger, George "Baby Face" Nelson, Charles Arthur "Pretty Boy" Floyd, George "Machine Gun Kelly" Barnes, Bonnie Parker and Clyde Barrow, and the Ma Barker Gang. Bureau Director J. Edgar Hoover's successes in this crusade made him the hero of law and order in the public mind. This historical analysis reveals the agency's often illegal tactics, including torture, frame-ups, and summary executions--later expanded throughout Hoover's 48-year reign in Washington, D.C., and exposed only after his death (some say murder) in 1972.