6. The Godfather (1972)
The Godfather is a cool anomaly in the fact that both the original novel and the film were written by the same writer. The novel was published in 1969 by Mario Puzo, who also co-wrote the 1972 adaption with the film director Francis Ford Coppola.
Both versions follow Michael Corleone as the lead character, in his journey from family exile to ruthless mafia boss. The movie is famous still for the incredible performances by Marlon Brando and Al Pacino.