'Machine Gun' McGurn is THE Hollywood role model for any gangster movie. He was a handsome character with an eye for the ladies - usually blondes. He liked to dress in fine clothes, parting his naturally curly black hair down the center, slicked back and straight. In action, he was just as smooth, mowing down his adversaries with his weapon of choice - the Thompson sub-machine gun.

He was born James DeMora and lead a good family life in Chicago up until the day the Genna gang of Chicago's Little Italy murdered his father for selling moonshine without the gangs approval. The legend goes that the young teenage Jack McGurn soaked his hands in the blood of his murdered father and swore revenge on his killers. Jack spent the next few years perfecting his aim with a gun, shooting birds on overhead wires with a small caliber rifle, and training as a boxer. He boxed as a welterweight for a time as Battling Jack McGurn but eventually went back to his vendetta against the Genna's and joined up with Alfonse Capone's gang of mobsters.

McGurn became one of Capone's top hit men, becoming especially adept in the use of the latest Mob acquisition - the Tommy gun. Thus, 'Battling' Jack McGurn became 'Machine Gun' Jack McGurn.

Jack was credited with over 25 known kills for the Capone Mob including 6 of the Genna gang - presumably those who had a hand in the killing of his father. In each of the murdered Genna's hands was found a nickel (5 cents), pressed there by McGurn to show his contempt of the men as "lousy nickel and dimers".

McGurn became a prominent member of the Capone Mob, with Capone not going anywhere without Jack close by. It was McGurn who held Albert Anselmi, John Scalise and Hop Giunta when Capone beat and murdered the three men for plotting against him. McGurn was also suspected of being the principal gunner and planner of the St. Valentines Day Massacre. Jack was arrested on suspicion of his involvement in the Massacre but the charges against him had to be dropped when his girlfriend, showgirl Louise Rolfe, swore that Jack had been with her at the time of the killings. The newspapers dubbed Rolfe "The Blonde Alibi". Her claims were later proved to be false and McGurn was charged with perjury. Louise Rolfe was to be forced to testify against McGurn in court, but Jack sidestepped that predicament by marrying Rolfe and, as his wife, she legally refused to testify.

McGurn had many legitimate ventures besides his gun toting ventures for Capone. He had part ownership in six or seven nightclubs. He spent so much money in nightclubs, it probably worked out cheaper to own them. At one of his clubs, The Green Mill, McGurn had contracted a rising comic star called Joe Lewis. When Lewis' contract came up for renewal, McGurn offered him a sweet deal including a $650 weekly raise. Lewis turned McGurn down accepting a better offer from a rival club called The New Rendezvous Cafe. McGurn was furious and told Lewis "You'll never live to open". Lewis did open but eight days later, he answered a knock on his door and was confronted by three men, two carrying pistols. The third carried a knife and proceeded to carve up the comic's face, neck and tongue. Lewis survived the attack but it took him ten years to learn how to talk again and climb his way back to the top of the nightclub comedy circuit.

When Capone went to prison for income tax evasion in 1929, McGurn's popularity began to wane. Although he was Capone's favorite, other members of the gang were not so fond of him. He was pushed out of a number of rackets and left with little left but his nightclub ownership. The clubs began to fold because of the depression and his "Blonde Alibi" wife, Louise Rolfe, dumped him too. He was finally reduced to getting by with some small narcotics deals. Narcotics was not a racket that the Chicago Mob condoned and on the eve of St. Valentines Day in 1936, McGurn was shot down by five men in a bowling alley. Two of the gun men were 'friends' he had entered the establishment with. In his right hand was left a nickel and besides the body was left a comic valentine which read:

This gave the newspapers plenty to speculate about - the nickel could implicate the surviving members of the Genna gang and the valentine could be a clue to the remnants of Bugs Moran's crew. More than likely, it was the work of some members of Capone's Mob who were tired of McGurn and wanted to leave some false leads for the police. The identities of the hit men are not public knowledge to this day.