In ‘Men in Black 3,’ Agents J (Will Smith) and K (Tommy Lee Jones) are back… in time. J has seen some inexplicable things in his 15 years with the Men in Black, but nothing, not even aliens, perplexes him as much as his wry, reticent partner. But when K’s life and the fate of the planet are put at stake, Agent J will have to travel back in time to put things right. J discovers that there are secrets to the universe that K never told him — secrets that will reveal themselves as he teams up with the young Agent K (Josh Brolin) to save his partner, the agency, and the future of humankind. Alongside Will Smith, Tommy Lee Jones and Josh Brolin, ‘Men In Black 3′ also stars Alice Eve, Jemaine Clement, Bill Hader, Michael Stuhlbarg, Nicole Scherzinger, and Emma Thompson. The film arrives in cinemas today.

How did the idea for ’Men In Black 3’ come about?

Barry Sonnenfeld: Will Smith, Tommy Lee Jones, Sony and I, we really enjoy doing these “Men In Black” movies. The issue was coming up with a concept or a plot for ‘Men In Black 3’ that would be worthy of going back again. One night, weirdly, while Will was shooting with me on ‘Men In Black 2,’ he said, “You know Barry, if we ever do ‘Men In Black 3,’ I should go back in time. Time travel to some other era, where I have to save Young Agent K, and in doing so the audience and I find out secrets about the Men In Black that none of us knew.” It sounded like a great idea. We all done that movie, ‘Men in Black 2,’ then we went off, did other things, and then over the ensuing six or seven years, Walter Parkes, the producer, and Sony hired a writer named Etan Cohen, who wrote ‘Tropic Thunder,’ and a first draft was written. I had nothing to do with the first draft, but I thought it was pretty great and I got involved with additional scripts and then directing it.

A big part of the previous “Men In Black” films is the chemistry between Will Smith and Tommy Lee Jones. With ‘Men In Black 3’ you’ve got the addition of Josh Brolin and the time travel element.

Barry Sonnenfeld: The relationships are incredibly strong. From Will Smith and Tommy Lee Jones, between Will Smith and Josh Brolin. And I think we also have more action than in ‘Men In Black 3′ than in ‘Men In Black’ and ‘Men In Black 2.’ Also, more Aliens and more magic. The audiences will be amused, amazed and also moved. I think if we can do all of those three things then we’ll have a really successful movie. With ‘Men In Black 3,’ it’s not only a “Men In Black” movie, it’s also a time travel movie. We wanted the movie to be both familiar and different. What’s familiar is the characters and premise of the Men in Black and who they are. We wanted to bring Will Smith and Tommy Lee Jones back together again. But we also wanted something new and inventive, and that came in the time travel element.

Josh, how did you build your own chemistry with Will?

Josh Brolin: When the camera roles, something happens. It was very nice, I hadn’t felt that with a lot of people. Usually you have to act at acting well. With Will Smith and I, something just happens when those cameras start rolling. And we’re very different people, but I think we are both very mischievous in our own way (laughs), so we were having fun with this kind of back and forth, cat and mouse thing. But it’s not a cat and mouse, it’s something different. It was follying, it was a lot of fun! We created our own thing so it became less about how am I going to do Tommy Lee Jones, more in finding a rendition of Tommy, and then making it our own, “Maybe K was this? Maybe he was happier back then? Maybe K is the lighter one, and maybe Will Smith’s J has gotten used to the K in the future and when he goes back in the past he’s taken on some of those curmudgeonly attributes?” Flipping things around.

Will Smith seems to have so much energy, how was it working with someone like that?

Josh Brolin: He’s got great energy man, that guy is a machine! He’s very professional and he’s there and he’s thinking about the story the whole time. He’s thinking about all the things….even though he didn’t produce the movie, he would be thinking all the things a producer should be thinking as well. I think it’s his natural inclination to do that. And then he has a blast on top of it, because he knows, like me, we’ve been doing it long enough to know if you’re not having fun doing it, then what’s the point? We had a lot of fun.

For a film like this, I can imagine you two naturally hitting it off and enjoying yourselves helping your performances?

Josh Brolin: Oh yeah. It’s one of those things, when you do the third one, the chemistry between Tommy Lee Jones and Will is so set, so electric – and you got that the minute the first one came out. It’s a hard thing to get in the way of. I think Will and I got very lucky, because the first time we met it was organic and immediate. Therefore I think that makes that dynamic more fun. Also, I think ’Men In Black 3’ being a fresh story, and also the fact that it has been ten years since the last one, I think that gave us the luxury of creating a new story.

How was it having Josh play Young Agent K? 

Barry Sonnenfeld: The performance was so consistent that it was really hard for me to tell where Tommy Lee Jones ends, Josh Brolin begins. And Josh Brolin ends, Tommy Lee Jones begins. I think when people watch this movie, they’re not gonna know that Josh was in the movie (laughs). I think they’ll think that the whole movie is played by Tommy Lee Jones because the entire movie is just this guy Agent K. It’s really hard to separate the two performances, whether it‘s 2012 or 1969, you‘re watching Agent K. The only person I thought would be right for the role was Josh. Also, I met Josh a few times because of knowing the Coen Brothers, being at various events where Josh was for ‘No Country for Old Men.’ So I knew Josh a little bit, I’d been around him, got a sense of him. And his role in ‘W.’ made me think that Josh was the guy.

You’ve also got Jemaine Clement as the films lead villain. He brings a lot to that performance? He’s both scary and funny.

Barry Sonnenfeld: In this performance, what surprises me about him is that he’s incredibly scary, he’s erudite, he’s mean, he’s funny, he’s gruff, he’s charming – all rolled into one performance as Boris. He has to sort of perform as if he’s learnt the English language as a second language. Yet still be understandable. We decided that he learnt it through British diction tapes. Jemaine brings a real slight Alien thing to him, which I think he had when he first came in initially (laughs). Jemaine must be an alien, because no one could go through the four hours of makeup he endured every morning and still be in a lovely mood like he was.

Was there a standout moment during filming for you?

Josh Brolin: The first scene me and Will shot was the first scene that’s in the movie with us together. When I’m sitting there looking at J, who’s looking around at all the 60s motif, and then he looks at me and he’s telling me something and I say, “How do you know my name?” That was the first scene we did in the movie, so that was an exciting moment for me because that’s a make or break moment. All the talking and the rehearsing, all of the studying we did, it comes down to that moment. It was the moment of, “Is this going to work or not?” That was a great moment.

Barry, I can imagine coming up with the 1969 look being a lot of fun, with the different technologies and décor?

Barry Sonnenfeld: Our inspiration for the 1969 Men In Black headquarters was the Johnson Wax building, designed by Frank Lloyd Wright. There’s that and we also created so much other huge, big, wonderful sets and gadgets – like the neuralizer, the 1969 neuralizer. I came from the angle of thinking that the difference between the technology in 1969, and the technology now, is just the size of the batteries. So everything in 1969 should be way too big, basically because it’s holding huge batteries. Everything from the neuralizer, to the Men In Black cell phone, they’re all too big.