On a recent Saturday, I drove to the Four Seasons in Beverly Hills to sit down with two of the architects of this year's first big summer movie.  Justin Theroux, the screenwriter of the film, is also known for his work in front of the camera, and the last time I saw him, he was wearing a ridiculous wizard's costume for his role in the David Gordon Green comedy/fantasy "Your Highness."

"I look a little different now, right?" he laughed.  "I was all Lazar-ed up last time."

We chatted about my reaction to the film and the first thing I brought up was the obviously improvisational nature of much of the work in the film.  I asked him about building structure and plot when things are that fluid on-set.  "It's not hard," he said.  "I'm not a novelist." 

He explained that he prefers a collaborative atmosphere.  "Moviemaking is a socialist endeavor."  His background as an actor prepared him for the idea that these things can change dramatically each day.  "I like writing.  I like that challenge.  If someone says, 'Oh, and Mickey wants a bird in this scene,' I want to be able to figure out how to do that."

I asked if it helps on a film like this knowing exactly who he's writing for.  After all, when you've got voices like Sam Rockwell and Mickey Rourke and Sam Jackson and Robert Downey Jr, why not make the most of their specific voices.  "It helps that I'm an actor and I know what actors hate to say.  They can sniff out exposition.  If anything, I did a lot of that for these guys, and it's a joy."  He talked about knowing Rockwell for 20 years in New York.  "I called him up and I was like, 'Dude, you're going to do this role.  It's great.  You're going to love it.'" 

He explained that the thing that is a mixed blessing about Downey is that he has so many different character voices he can use.  "Jon's job is to focus all of that heat and my job is to sort of ride the lightning.  And with Robert, he can get real bored after he says something one time."  He said the real trick on this particular production was learning how to make the process work for everyone.  It was really the second half of the shoot when they finally figured it out.

"It would be nuts to limit what really is one of the biggest gifts you have on the film, which is Robert and the amazing things that come out of his mouth."  He described his job as being the caretaker for story and theme, no matter what else was going on during the shoot.   I asked how it worked with all the Easter Eggs regarding the larger Marvel Universe, and how much latitude they're given to do that.  "Well, Nick and Scarlett were a total opportunity."  He said it was a given that Nick Fury would show up in this film after the teaser hidden at the end of the first movie.  "And once we decided on Black Widow, she gave us this great way in on this story."  He said the real trick is laying in opportunities that don't limit someone else.  "I can't sit in a room with the writers on 'Thor' or 'Captain America' while we build 20 movies.  It's just not feasible."  Instead, it's all about seeding the films.  "You don't want to screw over the next writer."

I asked how much contact, if any, he has with the team of Marvel advisors that includes Brian Bendis and Joe Quesada.  "We send the scripts to them in New York, sure, but Jon [Favreau] and Kevin [Feige] are really the final word.  Those guys are great, but they make comic books.  We make movies.  Their voices are valued."  He said more than anything, they serve as the test audience since these films don't go through the conventional testing process by design.  "These movies don't go through that process, and they're better for it."

And just like that, our time was done.

Next up?  Marvel's main man, Kevin Feige, and I'll have that interview for you as soon as possible.

"Iron Man 2" opens everywhere tomorrow.

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