Stark (Robert Downey, Jr.) is enjoying a Scotch on the rocks in the back of a Humvee when his convoy is attacked by, ironically, the very weapons that he manufactures. He's kidnapped by an Afghan warlord (Faran Tahir) bent on the domination of something-or-other. Anyway, the warlord and his militant group are bad guys who shoot a lot of innocent villagers. And they want Stark to build them their very own high-tech missile.
Stark's got a handy-dandy assistant and translator in Yinsen (Shaun Toub), a fellow captive and surgeon, who saved Stark's life by implanting some sort of magnetic contraption into his chest to keep the shrapnel out of his heart. Or something like that. The important thing to note is that Stark has a heart after all - even if it's full of steel and wires and scraps culled from weapons of mass destruction. As long as he's part machine anyway, Stark goes ahead and builds himself an armored suit...Witness the clanky, clunky, rusty, birth of Iron Man, whose mother was, it turns out, the necessity of invention.
The invention of necessity is the job of the storytellers; and in this story, tin man Stark grows a conscience to go along with that heart - to the surprise of all and the dismay of many, most of all Obadiah Stane (Jeff Bridges). Stane runs Stark Industries and keeps the board of directors happy while the hepcat's away. Certain plot twists involving the chrome-domed Stane will be evident to anyone familiar with the hairstyles of the rich and villainous. The flaw to Iron Man, although it's certainly not a fatal flaw, is that the plot hews to a fairly standard superhero origins storyline (with companion supervillain origins subplot) - which means that there are not too many surprises in that department.
On the other hand, screenwriters Mark Fergus and Hawk Ostby favor genuine dialogue and substantive and sometimes uneasy laughs over macho-posturing catchphrases, and there are plenty of unexpectedly complex pratfalls and hearty yuks in Iron Man. Director Jon Favreau (Elf) emphasizes character over action, which is, in the superhero action movie genre, a rare thing. (Don't worry: There's plenty of rapid-fire action in Iron Man too.) There are several terrific scenes in Iron Man that capture Stark and his compañeros in moments laden with personal history, with past disappointments and with unspoken feelings, and Favreau exhibits a light and lighthearted touch that gives the movie plenty of zing for the buck, to go along with all the bang.
I've always said that big movies need small stories, and the best parts of Iron Man are the little touches, the small details. It's what makes Iron Man a great fit for Downey - an actor at least as well-known for his checkered past and misspent youth as for his wunderkind talent. Downey gives genuine resonance to Stark's uneasy and complicated conflict between nascent morality and a natural gift for mayhem. The cast - which includes Gwyneth Paltrow as Stark's loyal and supercompetent personal assistant Pepper Potts and Terrence Howard as Air Force pilot/loyal friend/skeptic Rhodey - is particularly good, which means that Iron Man, like that custom-fitted suit of armor and armory, can be built around the characters instead of the other way around.
The gadgety hardware stuff in Iron Man is pretty darn cool, of course - Stark is a man who likes style and substance in his machines - and there's a lot of fun to be had in Stark's experimental phase and the frequency with which he falls to Earth (the movie certainly plays around with the Daedalus and Icarus mythology, although it's ice, not heat, that is Stark's downfall). But there aren't really any surprises in the movie's fight scenes (well, maybe a few). The best stuff is in the details, in all the little servos and gears and character alloys that keep this big picture moving as smoothly as that shiny metal suit.