Hook: Michael Corleone begins as an upstanding man who rejects his Mafia family’s corruption and violence as a clearly wrong and ultimately undesirable means to an end. Michael’s desire for normalcy beyond his crime family’s lifestyle is contrasted with his equally strong devotion to his father and siblings, hinting he will eventually succumb to the Lie that defending one’s family is an end that justifies all means.

Michael’s backstory is never explicitly explored, but we understand he was obviously raised in the heart of a crime family, by a crime lord father whom he loved in no small part because the man wanted better things for him and encouraged him to go straight rather than join the family business.

Michael’s Normal World is that of a smart and upright man who is moving away from his corrupt family into a promising new and legal life of his own, with his non-Italian girlfriend Kay being the clear symbol of the life he desires.

Inciting Event: Michael learns an assassination attempt has been made on his father, leaving him fighting for his life in a hospital. This causes Michael’s family feeling and loyalty to draw him back toward the criminal underworld.

First Plot Point: Michael sets up a meeting with the rival mobster and dirty cop responsible for shooting his father. Even though he is racked by nerves, he murders both men—irrevocably plunging him into the world of his family’s business, which he has striven to stay clear of up to now. He commits murder in his family’s defense. His new goal is to find his feet and survive in the dangerous new crime world he has plunged himself into.

First Pinch Point: Michael goes on the run in Sicily, hiding from his family’s enemies in the States. Although it’s obvious he will never be able to return to the life he formerly desires, he still has not completely committed himself to the life of a mobster. He is caught between worlds—between the old Truth and the new Lie.

Midpoint: When Michael’s brother Sonny is killed, he returns home to take over the leadership of his family. He moves from a reactionary role, in the wake of committing murder to avenge his father, to fully embracing the active role of his new destiny.

Second Pinch Point: Michael goes to Las Vegas and begins consolidating power for himself and his family in their war against the Five Families. Michael promises his second wife (and original girlfriend) Kay that he will legitimize the family business. He is still masquerading his new life under the old pretense that he can avoid being drawn into the realities of the Mafia.

Third Plot Point: Michael’s father dies, raising Michael to full and final headship of his family. He is king: he is victorious. But he is a criminal: he has sacrificed the Truth. Michael is now fully committed to his new lifestyle. He has internally come to peace with it, even as it demands greater and greater sacrifices of morality. No longer the boyish war hero, Michael has fully adopted the mantle of his family’s leader, in the wake of his father’s death.

Climax: Michael has become a far greater monster than his father ever was, unmitigated in the brutalities he is willing to commit, even down to murdering his brother-in-law on the very day he becomes his nephew’s godfather. He is victorious, but he has clearly sacrificed his soul.

Resolution: When Michael’s wife demands to know if he’s committed the recent string of brutal murders, designed to end the Mob war, he denies it—only to explicitly demonstrate the truth when he allows others to call him “Don Corleone” and close the door, symbolically, on the upright life he might once have made with his wife.

Note: Michael’s character arc is a Corruption Arc.