William "Willie" Sutton (June 30, 1901 - November 2, 1980) was a prolific U.S. bank robber. For his talent at executing robberies in disguises, he gained two nicknames, "Willie the Actor" and "Slick Willie." When not disguised, Sutton was an immaculate dresser.

Sutton was born into an Irish-American family in an Irish-populated neighborhood in Greenpoint, Brooklyn. He was the fourth of five children. He did not go beyond the 8th grade of school. To Mafiosi like Donald Frankos, William was a little bright-eyed man who stood at 5 feet 7 inches. He had a very talkative manner and chain-smoked cigarettes. He rolled his home made cigarettes with Bull Durham tobacco and dispensed mounds of legal advice to any convict intelligent enough to listen. Inmates considered Sutton a "wise old head" among the masses in the prison population. When incarcerated at The Tombs he never had to worry about assault or young ambitious criminals trying to prove themselves because his Mafioso friends like Donald Frankos looked after him. In conversation with Donald Frankos he would sadly reminisce about the violent and turbulent days of The Depression in the 1920s and 1930's while he was active in robbing banks. Throughout his professional criminal career he never actually engaged himself in violent behavior, but knew many stories from the time of The Depression and would always tell fellow convicts that in his opinion, during the days of Al Capone and Charles Lucania, aka Lucky Luciano, the criminal underworld was the bloodiest. Gangsters from the time period, and many incarcerated organized crime mafia family leaders and made Mafioso loved having Sutton around for companionship, although he wasn't like them at all. He was always a gentleman, witty and non-violent. Frankos declared that Sutton made legendary bank thieves Jesse James and John Dillinger look like amateurs.

Sutton married Louise Leudemann in 1929. She divorced him while he was in jail. Their daughter Jeanie was born the following year. His second wife was Olga Kowalska, whom he married in 1933. His longest period of (legal) employment lasted for only 18 months.