The earliest citation in the Oxford English Dictionary for the American usage of the term "G-man" was in 1930, from a biography of Al Capone by F. D. Pasley.
In popular legend, the term originated during the September 1933 arrest of the gangster George "Machine Gun" Kelly by agents of the Bureau of Investigation (BOI), a forerunner of the FBI. Finding himself unarmed, Kelly supposedly shouted, "Don't shoot, G-men! Don't shoot!", although this is probably a fabrication.[2][3]
The term was the basis of the title for the 1935 film G Men, starring James Cagney, which was one of the top-grossing films of that year.
Kelly's surrender is dramatized in the 1959 film The FBI Story. The encounter with Kelly is similarly dramatized in the 1973 film Dillinger. The film was followed by a 1974 television film titled Melvin Purvis: G-Man.
During Season 3 of That Girl in the 1969 episode "Many Happy Returns" Ann Marie is faced with a sudden audit from the IRS. She refers to the income tax person as a G-Man.
The Spanish Rock band Hombres G got its name in 1983 from the Spanish translation of "G-man" and after the James Cagney film G Men.[4]
In the Half-Life video game series (1998–), one of the main characters is a "sinister interdimensional bureaucrat" nicknamed the G-Man. Dressed in a suit and tie, and often carrying a briefcase, he speaks in a cryptic manner, and periodically intervenes to store or utilise the player character, Gordon Freeman, to shape events.
In the 2005 video game Psychonauts, G-Men appear as enemies in the level Milkman Conspiracy. They (poorly) disguise themselves as ordinary civilians as they tirelessly hunt for someone named the Milkman. The player must equip the objects that the G-Men use to disguise themselves in order to get past them.
The 2011 film J. Edgar includes a reference to the surrender scene in the 1959 film The FBI Story.
In the 2011 film X-Men: First Class, Charles Xavier refers to his team as the "G-Men", but Moira MacTaggart states that they are something different, and decides to name the team "X-Men". Charles finds the name amusing and keeps it.
In the 2013 game Grand Theft Auto V in the mission "Three's Company", Dave Norton claims that he'll "send some G-Men to [Franklin's] aunt's house".