Worst of the three. By far.

Rating: 3/10 (4 July 2010)

Many of the reviews of this seem too positive. The movie was deeply flawed and love for the early Godfather films should not blind us to the fiasco that was number 3.
Casting problems: Diane Keaton said all she needed to say in part 2. Her presence in the part 3 added nothing whatsoever. We learn from her dialog that she will always love Michael but that she will never accept his gangster ways. Yeah. We learned that in part 2. George Hamilton as the lawyer/confident. Lame. Sophia Coppola as Mary. She comes across like a dull-witted 16-year-old that doesn't know a thing about acting but thinks it is fun to be able to stand in front of a camera. (spoiler alert) the primary dramatic event of the movie involved her death. By that time I was hoping that she would be killed off (or at least get no more screen time), so my ability to feel any emotional impact at the death of this air-headed monstrosity.
Dialog problems: The dialog in Michael's study in the initial scene is painful to hear. The movie gets better, but very awkward dialog pops up every 20 minutes or so throughout the movie. Part of the problem is the screen play and part of the problem is that at times the actors don't know how to effectively deliver their lines.
Plot problems: Awkward casting & dialog aside, I think this is the biggest problem. when you get to be one of the wealthiest business men in the world, wacking people no longer makes any sense. When you have untold millions at your disposal, you find that you a wide range of tools to accomplish your aims, and most of these tools work better than bullets (anyone remember the last time a Fortune 500 CEO was taken out in a mob hit?). (spoiler alert) There is a scene in which one of the baddies flies a helicopter outside a penthouse ballroom in a high rise building and then occupants of the helicopter riddle the ballroom with machine gun fire killing dozens of wealthy business men. This would be par for the course in the Matrix, or True Lies, or Commando, but this type of violence is not part of the real world we live in. It's cartoonishness is at odds with the other Godfather films and makes it difficult to take this film seriously. As well paced and tense as the final opera house scene was, it was also in the category of cartooney violence. Did the best assassin in all of Italy really think the cleverest way to kill one of the richest men on the planet was to slip into a well guarded public place, kill off a bunch of hired body guards and then shoot a man in front of 1000 witnesses? Well, I guess the screenwriter thought so. The end result was a complete mess. The narrative flow of the final film was a train wreck. The plot elements went back from somewhat believable to overblown Hollywood insanity and back again.