Besides, casting Iron Man was easy compared with cobbling together the movie's script. Favreau began work with two newbie screenwriters but then brought in the scribes behind Children of Men to give the narrative some gravitas. He even got a script polish from Charlie's Angels scribe John August. Despite all that, Favreau began a four-month shoot last March without a firm script. Much rewriting was done on set, and much of it was driven by Downey, who's highly regarded for his in-the-moment inventiveness. ''There was definitely a pattern to Robert's choices,'' Favreau says. ''He was committed to making this as unique and real as possible.'' Downey says that movies now are often visually dazzling but are ''as dull as a bag of hammers.'' He wasn't about to let F/X outshine story. ''We set the bar high every morning,'' he says. ''And most of the time we met or exceeded it.''
Iron Man will give Downey a major career boost, provided it opens strong and garners some good reviews. Whatever the outcome, though, you sense that Downey's already cleared the highest hurdle. ''I'm not as prone to reckless abandon and self-centeredness as I used to be,'' he says. ''I literally have never had a better working experience in my life. And in many ways, it's an experience that's been a long time coming.''