Men In Black 3 will have "more action, aliens and magic" than the previous two films in the franchise.

The movie's director Barry Sonnenfeld believes the latest addition to the sci-fi comedy series has "something new and inventive" in the shape of a time travel element that sees Agent J (Will Smith) go back in time to the 1960s to stop an alien from assassinating Agent K (Tommy Lee Jones).

"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. 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," he said when asked what the chemistry was like between Will and Josh Brolin - who plays a younger version of Agent K.

Barry believes Josh's performance in the movie was so impressive that the audience won't even notice when the 44-year-old actor's portrayal of Agent K ends and Tommy's begins: "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. 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."