Michael Corleone is a fictional character that appears in Mario Puzo's novels and film adaptations The Godfather. In the films, the famous actor Al Pacino plays the character of Michael Corleone, and this character is one of the most famous and widely recognized characters in the world. Michael Corleone is the youngest son of Don Vito Corleone, the head of the Corleone family in New York. He has two older brothers, Sonny and Fredo, and a younger sister Connie. Corleone was introduced into the novel and the first film as being very different from the family's other people. The Corleone family is part of the Italian Mafioso residing in New York and Don Corleone is the strongest of all the other Italian groups. They are involved in certain illegal activities, what they call the “family business,” of which Michael has no part in since he has spent most of his adult life away studying at Dartmouth College and then into the United States army as a Marine who has fought in the Pacific Theater during the Second World War. He is a brave fighter and is awarded the Silver Star before being discharged from the army in 1945 as a Captain so that he is able to recover from his wounds. After the war, Michael comes back to Dartmouth and marries Kay Adams.
A few months later, an assassination attempt is made on Don Viro Corleone and this enrages Michael. This is where his transformation as a person and as a man begins. Michael comes to his brothers and offers to murder his father's would-be assassin Virgil “The Turk” Solozzo, and the police captain, Captain McCluskey, who ordered the Don's guards off their posts. Michael believes that the police captain did that on purpose, as he was also in on the plot to kill his father. This is another instance where we see a change in Michael Corleone with his aggressive and untraditional methods. The Mafia has a strict rule that calls for the protection of the police members, as they do not allow the members of the Mafia to harm the members of the police. However, Michael is able to convince his elder brother, Sonny, that McCluskey is acting as Solozzo's bodyguard, which means that he is protecting their enemy, and gets permission to proceed to murder the two men.
After the murders, Michael cannot stay in New York, so he flees to Sicily and lives there in exile for the next two years. He marries a young girl Apollina, but she is killed in a car bomb that was intended for him. His brother, Sonny is also killed in New York, and this is when he returns to take over the family business. This is where he encounters the skepticism of many of the family members, as they doubt his ability to lead the family. However, Michael is headstrong and he marries Kay, promising her that he will make the business completely legitimate within the next five years.
Michael's personality is depicted as a very brutal one where he uses clear-cut logic while making his decisions. He is ruthless as far as his enemies are concerned and does not even spare his own brother-in-law, who he finds to have plotted with other Mafia chiefs for Sonny's murder. Once he realizes that the other chiefs had arranged for his murder, he goes berserk and decides to kill as many as five other heads of the families. This establishes his power over the other families and puts the Corleone family back to the top. After these attacks, he gains the respect of his own family as well elicits fear from others, thereby establishing himself as the new Don, Don Corleone. Michael has a great ability to read people and he is very good with analyzing situations and preparing his own role within the outside influences. He is very sharp in his abilities and this is one of his positive aspects that allow him to succeed all the way to the top and take his family there along with him.
Thomas “Tom” Feargal Hagen, portrayed in the film by Robert Duvall, is an informally adopted son of Don Vito Carleone and his main place in the family business is to serve as the family lawyer, or the consigliere, which is Italian for advisor. He is considered as one of the brothers by the Corleones. He has been in the family since his childhood and he was Santino “Sonny” Corleone's best friend. Many critics have speculated that the character of Hagen is based on two actual mobsters Frank DeSimone and Murray Humphreys. Both these men were also lawyers/advisors for the Italian Mafia, but were very different from each other in their personality. Where DeSinome was involved in the illicit and violent activities of the Mafia, Humphreys kept himself in the background, just like Hagen's character. In addition, Humphreys was not born into the Mafia family but was adopted by Al Capone.
Tom Hagen had a rough childhood, as his real parents were killed when he was very little. He was thrown out into the streets and spent a lot of time alone on the streets in very deplorable conditions. Sonny Corleone ran into Hagen in the streets and feeling sorry for the boy, he brought him home with him. Vito Corleone took the little Hagen in and had him treated well. Hagen wanted to take the Corleone family name but Vito urged him not to do so for respect of his original family. Yet, Tom Hagen felt and was made felt like part of the family, and he also started considering Vito to be his father.
Hagen is completely faithful to the Corleone family and he is willing to go to great lengths to protect the family's name. He cannot refuse Vito anything and is always ready to show his respects for the family. When Vito sends Hagen to Hollywood to talk to a studio owner, Jack Woltz, so that he casts Vito's godson Johnny Fontane in his next film, he goes there without any question and tries his best to convince the studio owner. However, when the studio owner refuses Hagen, he decapitates the studio owner's most prized horse and places the head on Woltz' bed. This enrages the studio owner but he realizes that he cannot do anything about it legally and decides to cast Fontane in the end. This is where we see an aspect of Hagen's personality, where even though he is non-violent by his personal nature, he is willing to take that extra step in order to please the Corleone family, even if it means going against his peaceful nature.
Hagen also sees his share of violence when he is abducted by Turk and his bodyguards. Turk kidnaps him in order to convince him to convince Sonny to make the drug deal. Yet, even in this stressful time, he keeps his composure and tells Turk that what he is doing is wrong and that there will be extreme consequences of his actions. Turk threatens to kill Vito and Sonny, and this is what makes Hagen feel more guilty because he blames himself for the death of Sonny. When Michael Corleone takes up the place as Don, he relieves Tom Hagen of his duties as the family advisor and tells him that he is only to look at the legal businesses of the family in Los Angeles, Nevada, and Chicago. This is where we see another example of his unrivaled loyalty, as he does not mind this change and accepts whatever work is given to him by the family. However, when Vito Corleone dies, Michael calls Hagen back to the family's business in New York, where he again resumes his services as consigliere.