As "Iron Man" opens, with Robert Downey Jr. nursing a drink and talking a mile a minute in the back of a Humvee racing through the dunes of Kunar province, he's greeted with whoops of approval by the audience long before he dons the red and gold metal suit of his character's superheroic avatar.

But those whoops are quickly squelched when "Iron Man" gets down to the business of creation myth, which here is shifted from Cold War-era Vietnam to Bush Doctrine-era Afghanistan. For at least a half-hour, the film is veritably action-free, as the badly injured Tony Stark (Downey) is taken prisoner by a warlord who orders him to build a state-of-the-art weapon. Instead, Stark builds a suit of iron, the better to bust out of the cave and give his enemies a beat-down.

The real Iron Man doesn't emerge until Stark is back in California. He announces that his company is getting out of the weapons business, bringing a shadow of alarm to the face of his business partner, Obadiah Stane (Jeff Bridges). Thenceforth, "Iron Man" sets about the business of proving that plowshares can be as sexy as swords.

It succeeds only fitfully.

Toggling between Stark's impish goatee and Iron Man's full-metal body condom, and amid so many generic fireballs, kill shots and earsplitting thumps, bumps and crunches, the film finally collapses under its own weight. It's possible to see a decent franchise in "Iron Man" with Downey at its troubled center; the key is getting rid of the scrap metal.

-- Ann Hornaday (May 1, 2008)

Contains intense sequences of sci-fi action and violence, and brief suggested sexuality.