In early 1933, J. Edgar Hoover clung tenuously to the bureaucratic fiefdom he had inherited nine years earlier as a young Justice Department lawyer: the Department’s Bureau of Investigation. Despite his success at turning the Bureau into a professional force, it was constantly under threat from politicians looking to replace him with a more graft-friendly chief. Meanwhile, criminals, outgunning and outdriving the cops, were quickly becoming folk heroes. By June of that year, the situation had come to a head: In Ohio, an ex-con with a crooked grin named John Dillinger robbed his first bank. In Missouri, Pretty Boy Floyd, on his own robbery romp, kidnapped a county sheriff. In Texas, Clyde Barrow and Bonnie Parker were just coming off a crime bender of their own. And in Kansas City, an ill-advised attempt by members of the Barker gang to spring one of their members from police custody ended in a massacre, killing five, including a federal agent. In his new book, Public Enemies: America’s Greatest Crime Wave and the Birth of the FBI, 1933–34, Vanity Fair correspondent Bryan Burrough explains with verve how the Midwestern crime spree birthed the modern agency, re-creating pivotal scenes from the Kansas City massacre to Dillinger’s death in front of a Chicago theater. Burrough shows how, within two years, Hoover had quietly and methodically accumulated the power that made him untouchable by any politician until his 1972 death. Burrough reads at 7 p.m. Wednesday, July 28, at Olsson’s Books & Records, 418 7th St. NW. Free. (202) 638-7610. (Mike DeBonis)