Part II is two hundred minutes in length, but the film seems to pass more quickly. Set in the 1950s, the story picks up soon after The Godfather left off: Michael Corleone has moved some operations to Las Vegas, but remains involved in New York organized crime. He also seeks to expand operations to pre-Castro Cuba, in partnership with aging, chronically ill Hyman Roth (Lee Strasberg). He also has to defend himself against congressional hearings into his criminal activities. As in the first film, Michael ruthlessly punishes those who oppose or betray the 'family' (i.e. himself). Although his success continues, he also becomes ever more cold and distant; nearly a personification of evil. The only emotions that remain are the desires to punish those who have hurt him.
There also flashbacks of Michael's father Vito first as a boy, then as a young man. Vito (De Niro) immigrates to America, alone, to escape a vendetta against his family. Although he can be as ruthless as his son would later be, Vito also rewards with favors those who are on his side. Since the people he kills seem to deserve it, Vito comes off better than Michael does. De Niro's detached cool provides a welcome break from Pacino's relentless gloom, and it was wise of Coppola to shuffle the two films together despite the film's length and the disturbance of continuity.
Those who believe that Troy Donahue never made a good film stand corrected. Donahue has a small role as Talia Shire's fortune-hunting suitor. Michael V. Gazzo, who has a marvelously raspy voice, has a great supporting role as troubled mobster Frank Pentangeli. As in the first film, John Cazale and Robert Duvall provide excellent performances.
One wonders why the first two Godfather films are so much better than The Conversation, another film from 1974 directed and written by Francis Ford Coppola. Part of the reason is that Gene Hackman's character, and character evolution, is less believable than Al Pacino's. The supporting characters and story in the first two Godfather films are also better.
The Godfather Part II also won Academy Awards for its score, co-credited to Nino Rota and Carmine Coppola (Francis' father), and for its sets.