Continuing Sony’s wondrous marketing for their 2012 tentpoles, Barry Sonnenfeld (perhaps lacking anything insightful to say about filmmaking, his career or the junk he’s peddling) simply summarizes most of Men in Black III to MTV:
Agent J needs to go back in time to save Tommy Lee Jones’ [character] from some event that’s happened decades earlier. He needs to learn something about Tommy’s character that he didn’t know before.” That was the genesis. Ten years later, we’re about to come out and show the world what that meant.
In the first act, Agent J is a bit fed up with how closed K is as a person, how he feels he needs to open up and communicate more, but it’s not happening. K says to J, “You know how I live such a happy life? I don’t ask questions I don’t want to know the answers to.” At the end of the first act, Jemaine’s character, Boris the Animal, breaks out of prison and finds a guy who has a time device. He says he’s going back to 1969 to do something to the man who shot off his arm – because Boris only has half an arm – and of course, that man is Agent K. At the end of that first act, Tommy’s character disappears, and no one remembers that he ever existed… except Agent J, who realizes that someone went back in time and did something to Agent K. So he has to track down who gave Boris the device, and travel back to 1969 with one warning: He has to stay away from his old partner.
What happens, actually, is he gets arrested by Agent K – now Josh Brolin – in 1969. The second and third act is all about tracking down Boris and Will renewing his friendship with a different K than the K he knows from 40 years in the future. What’s really cool is that J is constantly wondering why this guy who seems sort of open and happy became the sort of curmudgeon that has been his partner for the last 14 years. He makes a discovery about that. So, “Men in Black 3” is by far the most emotional of the movies. It has a really surprising ending.
The fantastic thing about “Men in Black 3” is that it totally closes out the trilogy, it answers questions that you didn’t even know you should be asking, it leaves you emotionally warm and sad and happy, and it could also reboot the franchise. But I can’t even begin to tell you how to interpret all of that. [Laughs] But I would say this: If your interpretation is that “Men in Black 4” will only star the worm guys and Frank the pug, you are wrong.