Aniello John "Neil" Dellacroce (March 15, 1914 – December 2, 1985) was an American mobster and underboss of the Gambino crime family of New York City.

Dellacroce sometimes walked around Manhattan dressed as a priest and called himself "Father O'Neil" to confuse both the police and rival mobsters.

[7][better source needed] According to records from the Knapp Commission, which investigated police corruption in a number of industries beginning in 1970, Dellacroce and other mobsters were involved in after-hours bars that catered to homosexuals in the West Village, Manhattan.

[8] In 1971, Dellacroce was sentenced to one year in state prison on contempt charges for refusing to answer grand jury questions about organized crime.

In return for labor peace, the Yankee Plastics Company of New York gave Dellacroce 22,500 stock shares worth $112,500.

Gambino appeared to believe that his crime family would benefit from Castellano's focus on white collar businesses.

Castellano arranged for Dellacroce to remain as underboss while directly running traditional Cosa Nostra activities such as extortion, robbery, and loansharking.

[14] While Dellacroce accepted Castellano's succession, the deal effectively split the Gambino family into two rival factions.

[18] On March 28, 1985, Dellacroce, along with his son Armand and eight others, was indicted on federal racketeering charges regarding the activities of two crews in New York and Long Island.

[17] On July 1, 1985, Dellacroce and the other New York Mafia leaders, pleaded not guilty to a second set of racketeering charges as part of the trial.

A planned meeting of Castellano with other Gambino mobsters at Sparks Steak House on December 16, 1985 was chosen by Gotti as the opportunity to have him killed.

In perhaps the film's most memorable scene, Keach as Dellacroce teaches Travolta's Gotti the names of the five boroughs of New York City.