The nail-biting life of an action film director

July 12, 2012, 2:57 PM UTC

FORTUNE — Directing a movie requires more than sitting in funny chairs and yelling “action” on a set. Directors need to intelligently discuss finance, set production, and acting all in a day’s work.

Simon West is multilingual in the way directors must be. He’s a big-picture action director whose latest project is Expendables 2, a shoot-em-up that’s hitting theaters this August. He was also the man behind the camera for The General’s Daughter, Lara Croft: Tomb Raider, and Con Air.

He recently spoke with Fortune about what it takes to manage the many moving parts of a big picture. After over a decade in the business, West says, he’s finally starting to have some fun.

Fortune: What does a day in the life of an action movie director look like?

Simon West: Even my family members don’t really know what the day is. They see directors on TV shouting, “action” and “cut,” and they think it’s mostly about directing traffic.

But in one day, I can be talking to the accountant about how we’re going to stay on budget, then a technical guy about how we’re going to make it look like a plane is really flying over the building — we’re talking physics and engineering. By the end of the day, I’m talking to an actor about what his feelings are. So I’ve gone the whole gamut in one day from money to engineering to art to emotions.

How do you coax actors to give genuine, emotional performances on an action set?

I make them feel them comfortable because, ultimately, I’ll get the best performance that way. You have to learn everyone’s personality because all of these people are human beings and everyone has a different psyche.

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I have this memory of a scene I did for Con Air with John Malkovich, Nicolas Cage, and John Cusack, and they all had completely different styles of acting. In action movies, you don’t really rehearse that much. The actors come on, run through it, and then you shoot, so I had to learn their styles very quickly.

I soon learned that John Cusack likes to do as many takes as possible, then run around to the back of the camera, then do it again. Nicolas Cage would come in and do his scene, and he’d been thinking about it very hard for days before, and he knew exactly how he wanted to do it. Then John Malkovich would do take after take, and he would do it in a completely different style. One minute, he’d be doing it in a little child’s voice, and the next minute, in aNew Yorkaccent. It was so different, that I had a huge choice with his scenes.

Are there any scenes that you are most proud of?

In The General’s Daughter, there were two scenes that are quite important. One is with John Travolta interrogating James Woods. It was very cleverly written by Scott Rosenberg. This scene was so good that I thought the best thing I could do would be to not do very much at all.

I told James Woods that I just wanted him to sit down face to face with John Travolta, and he did it from top to bottom beautifully. You could tell how good it was because the whole crew went silent. And that carried through right through the screening.  That was a scene that went from writing to shooting to right in the film as near perfectly as I could probably wish for.

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Funny enough, there was another scene like that. It was the last scene in the movie and the sun was going down and, by chance, mist had come rolling in over this river. It was one of those shoots where every single thing had gone perfect, technically and emotionally, with the actors and everything. At the end of the day when I screened it, the audience hated it.

I think it’s the only scene I’ve ever shot where I thought, “That’s perfect.” And I had to cut it out.

That sounds brutal.

I hate to cut things out. Filmmaking is so hard and you put so much into it, cutting stuff out is heartbreaking to me. I know other people work differently, but I work and work in preparation. If am going to do the scene, then I’m going to make it work, you know, goddamnit.

How do you get your crew to move as a cohesive unit?

When you start out, it can be very stressful because you’ve got no track record, you’ve got everything to prove. The dark version is it’s the wolf pack and you’ve got to be the alpha male. And if the pack senses any weakness, they’ll rip you apart and eat you.

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You have to be a strong leader — not a cruel leader, but you definitely have to be a strong leader. Because you expect all these people to follow you up the mountain, carrying heavy equipment, and through the whole film, they’re dedicating their careers and a year of their lives to you. You had better be able to lead them to victory.

That sounds stressful. Do you ever get to have any fun, or give a big fist-pump after you pull off an awesome explosion?

Yeah, that does happen, and it is great, and it’s nail-biting up until that moment. Sometimes it’s better than you even expected, and that’s a spectacular event.

But I’ve been in situations like that where I’ve seen it with my eyes and it’s the most fantastic thing in the world, and then I’ve turned around and someone in the crew says, “well, three of the cameras jammed on that, the other one was out of focus, and the other one misted.” You’re constantly dealing with disappointment.

But now, I have less to prove, so I try to enjoy the people around me. I do find that watching great actors in front of the camera when I’m doing actually very little is probably when I’m happiest.