In New York, James 'Brick' Davis was a poor boy that the mob kingpin 'Mac' McKay paid his college tuition at the Law School without requesting anything in return but be a honest man. His best friend and roommate at college Edward "Eddie" Buchanan visits him at his office and gives an application form to the Department of Justice, since he knows Davis's business is weak because he is an honest man. When Eddie is murdered by gangster, Davis fills the application form and sends to the FBI. He is hired, travels to Washington, but soon he has relationship problems with his trainer Jeff McCord. When the chief of the Bureau, Gerard, assigns a team to hunt down Buchanan's killer, Davis wants to join the team, but he has not completed his training yet and Gerad refuses. Davis sees Jeff's sister, the nurse Kay McCord, he puts his eyes on her, but she does not pay attention to him. Meanwhile 'Mac' McKay retires from the crime life and buys a resort to work honestly for the rest of his life. Davis identifies one criminal, Danny Leggett, in an open case and the criminal is arrested by the agents. But soon the agents that are escorting him are murdered by the mobsters and Leggett flees. After a slaughter of agents, the laws change, and the G-Men are allowed to have guns to fight the organized crime. Now McCord sees that Davis is an important agent and assigns him to take down Leggett and his gangsters.