Serpico is a 1973 American biographical crime drama film directed by Sidney Lumet and starring Al Pacino in the title role.

The screenplay was adapted by Waldo Salt and Norman Wexler from the book written by Peter Maas, with the assistance of its subject Frank Serpico.

The story details Serpico's struggle with corruption within the New York City Police Department during his eleven years of service, and his work as a whistleblower that led to the investigation by the Knapp Commission.

Forced to accompany officers as they collect payoffs from criminals and small businesses, Serpico refuses to accept his share of the money.

Serpico and his well-connected friend Blair go to the mayor's assistant, who promises a real investigation and support but is stymied by political pressure.

Blair uses his connections to arrange a personal interview with the district attorney, who tells Serpico that if he testifies to a grand jury, a major investigation will follow.

[5][6] Detective David Durk, who also appeared in front of the Knapp Commission, planned to sell the rights of their story for a film adaptation.

Salt's work did not satisfy Avildsen, who threatened to leave the project unless he could bring Norman Wexler to write the screenplay.

Avildsen had insisted on a meeting with Bregman and De Laurentiis to shoot a scene in the real home of Serpico's parents for authenticity.

[21] Avildsen's account for the reason of his dismissal was that he refused to cast Bregman's then-girlfriend (and later wife) Cornelia Sharpe as Leslie.

Pacino had learned Salt's screenplay, and he agreed with Lumet that Wexler's revised version improved the structure, but that the dialogue was impoverished.

[30] Lumet focused on portraying Serpico's struggle to balance his work and personal life, and his increased isolation and alienation, as his efforts produced slow results.

To inform of the progress of the sessions and possible changes on the arrangements, James flew to the cities where Theodorakis appeared to work the details.

[46] New York City Police Commissioner Michael Codd stated that the film "tends to imply that Serpico was the only honest cop in the whole department".

Durk stated that the end of the film conveyed that "the cost of honesty is martyrdom", and Serpico's departure for Switzerland showed him "wounded and frustrated".

[50] A follow-up critique by the publication deemed Pacino's acting a "masterful performance", as the reviewer remarked that "he walks like a cop.

It criticized the focus of the film on Serpico, and the minor role that the screenplay writers gave to the character that represented Durk.

Salt and Wexler's screenplay was hailed as "almost documentary reality",[56] and its treatment of the main character "a complex and evolving portrait".

[58] Champlin felt that Allen's work was considered to be "high on the list" for an Academy Award nomination, and deemed Theodorakis's music "effective".

Pacino's performance was called "riveting", and the piece praised the "sharply individualized characterizations" by Tony Roberts, Jack Kehoe, John Randolph, Biff McGuire, Barbara Eda-Young and Cornelia Sharpe.

[61] Meanwhile, also for Philadelphia Inquirer, investigative journalist Greg Walter lamented its portrayal of police officers as "snarling, insipid ass(es)".

[64] The Detroit Free Press suggested that Serpico would be a breakthrough role for Pacino as an actor, and called his work "fascinating".

[67] For The Evening Sun reviewer, Lou Cedrone expressed his doubts about Durk's "gratis talk of defamation of the police image".

[72] The Kansas City Star detailed the criticism that the film received from police officers, and Serpico's discontent with the production.

[73] The Times in Shreveport, Louisiana, opened its review applauding Serpico's denunciation of police corruption, while it pointed out that the film "exceeds (the) expectations" of the viewers for it to be "powerfully dramatic".

[78] In its later review, The Village Voice declared that the "Watergate-era time capsule of hippie fashions" that the film presented "ought to look pretty dated", but that the story "feels depressingly relevant".

[85] A television series based on Maas's book and the motion picture was broadcast on NBC between September 1976 and January 1977, with David Birney as Serpico.

[93] In the 2007 episode of It's Always Sunny in Philadelphia "Bums: Making a Mess All Over the City", Charlie imitates Pacino’s performance after the gang buys an out-of-commission police car.

The film is referenced in a 2016 episode of El ministerio del tiempo as the reason for the nickname of one of its main characters, "Pacino".

[96] Pacino's role as Frank Serpico ranks at number forty on the American Film Institute's AFI's 100 Years...100 Heroes & Villains.