The happiest contest in the world is between GF and II. GF has Brando, and Pacino's great transformation, plus Castellano. II has more sweep, plus Gazzo and Strasberg. Both have Duvall and Cazale. Everytime I think that the opening scene of GF is the pinnacle, I watch the Havana sequence in II, and change my mind.
I guess if you put me up against the wall, I'd say II. III isn't in the running.
Good points TB. IMHO The Godfather was a ground breaking film, and some of it was shot during a time when neither FFC nor Al Pacino knew for sure Paramount wasn't going to fire them. It had such a profound impact when it came out, there have been few movies like it ever. Stylistically, I can see how one may view GF II as a better movie. I think in some part this is due to the fact that FFC and Pacino had more confidence, and FFC had matured as a filmmaker.
III is so difficult to peg. Agreed it is not in the running, but despite its flaws I'm glad it was made.
