Gazzo was nominated for a Best Supporting Actor Oscar for his performance, which he lost to Robert De Niro, his co-star from the same film (as young Vito Corleone).

Frank is a caporegime in the Corleone family, running the family's operations in New York City while Michael Corleone (Al Pacino), his brother and underboss, Fredo (John Cazale), consigliere Tom Hagen and the other two capos, Rocco Lampone (Tom Rosqui) and Al Neri (Richard Bright), are based in Nevada.

Pentangeli's character was created in The Godfather Part II by Coppola and Puzo due to actor Richard Castellano not reprising his role as Clemenza in the sequel.

[1] Near the beginning of the story, Pentangeli approaches Michael to ask for his help in eliminating the Rosato brothers, rivals in New York, who claimed to have been promised territories by Clemenza prior to his death.

Michael refuses, however, and orders Pentangeli to do nothing, as he does not want a war to interfere with an upcoming deal with Hyman Roth (Lee Strasberg), who supports the Rosatos.

Most damningly, Cicci tells investigators that Michael personally killed Captain McCluskey and Virgil Sollozzo (portrayed by Sterling Hayden and Al Lettieri respectively in The Godfather), and also began planning a mass slaughter of New York's other Mafia bosses as early as 1950.

Frightened, Frank recants his earlier statements, saying he "told the FBI guys what they wanted to hear," and now claims that the Corleone family is innocent of any wrongdoing, thus perjuring himself before the Senate committee.

[2] An early draft of the film's script explains that Vincenzo, shocked that his brother is about to betray the Corleones, attends the hearing to remind Frank that he must not break the Mafia's code of silence, omertà.

His brother's presence, as well as the stare they exchange, serves as a threat that if Frank follows through with his planned testimony, retribution will be taken against his children, who are living in Sicily under Vincenzo's guardianship.

[3] This character made the national news on January 25, 2019, because he was referenced in the federal indictment of President Donald Trump's longtime adviser Roger Stone.

The filing goes on to say, "Frank Pentangeli is a character in the film The Godfather: Part II, which both Stone and Person 2 had discussed, who testifies before a congressional committee and in that testimony claims not to know critical information that he does in fact know.