Superhero movie follow-ups have been a tough business lately. "Iron Man 2" marks Marvel's first sequel since "Spider-Man 3" left millions disappointed in 2007. So to quell any lingering fears, "Iron Man 2" is not a letdown. It's far from it. To think director Jon Favreau and star Robert Downey Jr. would lose sight of what they did that turned a lesser Marvel character into a multi-million-dollar franchise would be a gross underestimation.

Downey Jr. does not relinquish Iron Man's reputation as the wittiest superhero ever brought to the big screen. "Iron Man 2" provides just as much of a humorous joyride as the 2008 film, backing up all the subtly outrageous dialogue with superb visual effects and action that seizes all attention. It all still works because Favreau has locked down the blend between not taking the story too seriously but still telling it with conviction.

But oh yes, "Iron Man 2" complicates things a bit. Self-outted billionaire superhero Tony Stark aka Iron Man has a lot on his plate from government subpoenas asking him to hand his suit over to the people to a private matter: his fake heart -- the arc reactor -- is slowly poisoning him. Feeling like it all might cave in on him, Tony makes his assistant, Pepper Potts (Gwenyth Paltrow), Stark Industries' new C.E.O.

Screenwriter Justin Theroux ("Tropic Thunder") accepts the responsibility of weaving these plot lines in with three new significant characters. Mickey Rourke assumes the villain role: silently vengeful Russian physicist Ivan Vanko, who after a failed attempt at using his own whip-toting arc-reactor suit to kill Tony in the film's first action sequence on a Monaco raceway, finds himself in the employ of Tony's arms-dealing nemesis, Justin Hammer (Sam Rockwell). With Tony going in and out of the public's good graces, Hammer uses Vanko to create droid soldiers for the military, which would effectively make him the real "American hero." Scarlett Johansson goes redhead for a supporting role as one of Tony's new assistants who is more than she appears to be.

The busyness continues because of Marvel's commitment to an eventual "Avengers" film in 2012 combining Iron Man and heroes of future Marvel films. Samuel L. Jackson appears as Nick Fury, director of S.H.I.E.L.D, looking to recruit Tony for his team and nudging him in the right direction as Tony's deceased father, Howard, holds the answer to his "heart condition."

The overcrowding, however, never gets the best of "Iron Man 2." Theroux has designed the story to move along quickly and effectively, letting the action and the humor carry the entertainment factor evenly throughout the film. The unfortunate trade-off is that very little resonates about "Iron Man 2." Tony's attempt to find a new core element for his arc reactor is the one true through-line. Everything else from Tony's feuding with Pepper and his buddy Jim Rhodes (Cheadle) to Hammer's frustrations with Vanko's progress to Nick Fury all act in service of the plot. The element of Tony's irresponsibility and alcoholism, perhaps the greatest potential of the film to make any kind of statement, appears in only a couple brief scenes. Downey Jr. and Favreau give us many great Tony Stark moments, but he doesn't have a chance to grow -- just make us laugh and remember how great a character he is.

And honestly, how great a character he is. Downey Jr.'s shtick hasn't gotten old in the least despite his increased exposure the last two years and the writing caters to him even more this time around. Maybe a lesser actor playing a lesser character wouldn't be able to lift up a busy superhero story with this many subplots, but RDJ has that ability. With an imaginative visual effects crew at his back and a director who knows how to condense action and make it count, he'll likely continue providing easy-to-love action entertainment as Iron Man no matter how many different chinks these films develop in their armor.

-Steven C

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