In the latest film in the franchise about the exploits of two secret agents who maintain order among aliens living on Earth disguised as humans, Smith's Agent J must travel back in time to 1969 to save his partner, Agent K, played by Jones in the present and Josh Brolin in the past.

Sonnenfeld spoke to Reuters about the latest collaboration, the addition of Brolin to the cast and the three films.

Q: The last "Men in Black" film came out 10 years ago. What took so long?

A: "I don't know exactly why this one took 10 years ... The funny thing is, the idea for 'Men in Black 3' is based on an idea that Will pitched to me while we were on the set of 'Men in Black 2.' One night Will said, 'It would be fun on the next one for me to go back in time and save Tommy Lee Jones from something that happens to him in the past, which makes Tommy Lee Jones dead in the present.'"

Q: How did Brolin pull off such an uncanny performance?

A: "Many people ask me if I dubbed Tommy Lee's voice over Josh's performance, which we didn't do. Josh watched all of Tommy's movies. He had a tape recorder on the set which he would listen to of Tommy's performance in the first two movies. He just channeled him."

Q: Did you worry that maybe too much time has passed between installments and audiences won't remember the previous films?

A: "Since it will have been 15 years since the first one, in some cases kids who loved these movies are now adults and are going to be able to bring their own kids to this one. The previous films have had a really great life theatrically, on DVD and on television, so I think people are excited to see this one. Agent K and J are a beloved couple that audiences look forward to seeing again. There's a lot of love between the two characters, although it's never expressed."

Q: Much has been reported about how difficult the entire production was - how it started shooting before there was a completed script and a built-in hiatus that dragged on longer than it should. What are the facts?

A: "It's not nearly as big a deal as people think it is. We needed to start shooting when we did for several reasons. One was (to take advantage of) the tax investment credit from New York State (that was going to expire). Secondly, Will Smith had been circling several movies and we wanted 'Men in Black 3' to be his next movie."

Q: But isn't shooting without a completed script a Hollywood no-no?

A: "We had a script and knew where we were going, but only the first act was ready to shoot. So we shot the first act up until just before Christmas. We scheduled the movie to have a several-month hiatus because the other acts still needed additional pre-production. So instead of coming back from Christmas break two weeks later, we came back and started preproduction on those next two thirds of the movie. We didn't start shooting for another six or eight weeks after that."

Q: What were some of the issues that needed to be addressed?

A: "The biggest challenge when doing a time travel movie is to lock down all the rules of time travel so the audience understands them, appreciates them and buys into them. We spent many evenings watching 'Back to the Future,' which is the best of the time travel movies, to see just how brilliantly they pulled that off. We didn't want to paint ourselves into a time travel corner."

Q: What lessons did you learn on the first two that you could apply here?

A: "On the second one we tried to be too funny. The franchise works beyond the fact that it's a comedy. If you look at the first one, it doesn't play as a comedy. There are funny scenes but it's observational, like Will being thrown around by a pregnant alien with tentacles in the background of a shot. It's not that someone is saying funny things. It's about the characters and the chemistry between them."

Q: So how is the third one different, besides being in 3D?

A: "This is the most emotional of the three movies. We learn stuff about Agent J and K at the end of the movie that we don't see coming."

Q: After 15 years and a couple of kids, has time mellowed out the energetic Will Smith?

A: "He's still as hyperactive as he's ever been. He's like a six-month old Great Dane puppy. He's got way too much energy, he's way too happy and he's way too rambunctious. He never stops."

(Reporting By Zorianna Kit)

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