Story of how a group of incorruptible federal lawmen helped put 1920s' Chicago gangster Al Capone in prison.
G-men grab a gangster and a governor thanks to a clerk in the fingerprints division.
Having paid for the education and legal training of his younger brother, Bruce, with the idea that he would become a lawyer and join his business, Frederick Garth, a racketeer posing as an honest businessman, is dismayed when he learns that Bruce has become a G-Man instead.
The actions of various criminals such as Dillinger, Pretty Boy Floyd, Bonnie and Clyde and Baby Face Nelson are reenacted in this film.
By a daring ruse and inside help, Pete Rennick, a noted criminal behind bars on federal charges, escapes from the prison, and all of the law-agencies and local police are out to catch him with roadblocks and every car searched, but the escapee gets away. Bill Hasford, a private detective, investigating a racket finds it leads to the wanted man, and has the biggest adventure of his career.
He battled the Kennedys and Martin Luther King, encouraged McCarthy and single-handedly changed the course of history. Hired by F.D.R. to be the director of the FBI, Hoover erected the most sophisticated investigatory agency in the world.
G-Men in Washington break up a powerful spy ring and capture the ringleaders.