Plot holes: The Chairman of the Senate Investigating Committee asks Michael, "Is it true that in the year 1950, you devised the murder of the heads of the so-called Five Families in New York?" But at the party in the opening scenes, which takes place in 1958, Kay reminded Michael that, seven years previously, he had promised her that "within five years, the Corleone family will be completely legitimate." If that conversation took place in 1951, then the murders the Chairman referred to, which came afterwards, could not possibly have happened in 1950. In fact, since Michael refers to his son (who was neither born nor even conceived in 1951) being three years old shortly before the murders, it is probable that the murders did not occur before 1955.
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