Excellent mafia movie: Godfather

The Godfather is a movie in 3 parts, with the first 2 movies being the most acclaimed, and the 3rd one being not quite considered in the class of the other 2. The Godfather was the first movie to take an indepth look at the world of the mafia from the perspective of the desires / ambitions of individual mafia members. In that sense, it was a revolutionary movie. The Godfather was an incredibly successful movie, being the all time grosser soon after release. The movie was made in 1972, based on the novel of the same by Mario Puzo, and was directed by Francis Ford Coppola. It starred a host of names who became very successful - Marlon Brando (Vito Corleone - the founder of the family), Al Pacino (Michael Corleone - the true inheritor), James Caan, Robert Duvall, Diane Keaton, and a host of others. It won 3 oscars as well.
The Godfather captures the life of Vito Corleone, and the passing on of the baton to his younger son Michael, the quiet one of the family, and the most ruthless in his own way. Movie starts with the marriage of his daughter, and the Don is receiving requests from people (including one person whose daughter was exploited. When the father went to the court, he lost, and came to the Don for justice). The Don's whole family is there on this day, including his younger son Michael who is a war hero and is not part of the family business.
Another close friend is the singer Johnny Fontane who has been rebuffed in his attempts to get a key role, and the Don dispatches his consigliere to help him (a brutal sequence where the movie moghul gets a message with the head of his horse placed in his bed). The bad time for the family starts when the Don refuses an offer by heroin dealer Virgil Sollozzo (The Turk) for a share in the business in return for political protection and financing. This leads to an assassination attempt on the Don, his counseller kidnapped and the family executioner killed. There is now the prospect of an all-out war with the other families.
In a event that turns Michael's life, he visits his father in hospital, but realizes that a crooked police captain has removed all the security. Michael manages to save his father, but gets his jaw broken. Michael, in a massive change, now offers to kill The Turk and his police captain for purely business reasons. After some discussion, this is agreed to, and logistical planning happens. Michael manages to carry out the deed and escape the country. In the time that he is out, his elder brother is set up his sister's husband and killed by machine gun. Michael, in exile in Sicily, meets a beautiful girl, Apollonia, marries her, but she gets killed in an attempt on Michael's life.
The Don has to bring his son back from Sicily, so he makes peace with the other families, and gets Michael back. Michael is now in charge, and marries his old girlfriend, Kay.
It is now that the ruthless planner starts to emerge. The Don has slowly transferred all his contacts to Michael, who is now the true Don. When Vito dies, Michael is approached for a truce by one of his commanders, Tessio, thus marking his as a traitor. And then Michael schedules his counter-attack. On one day, during the baptism of his nephew, Michael arranges for the murder of all his enemies, including his sister's husband. When Kay confronts him with this, he denies any responsibility. But when she sees him being honored as the new don, she realizes that he is indeed responsible.