In the vast pantheon of iconic movie sequels, it's safe to say that some titles will forever be immortalized in our collective consciousness; obvious national treasures such as 'The Empire Strikes Back,' 'The Godfather Part II' and 'Breakin' 2: Electric Boogaloo' spring immediately to mind.

Will 'Iron Man 2,' which opens Friday, join the ranks of the celluloid untouchables, indelibly etched into our pop cultural landscape for its contribution to film as an art form? Probably not, but one thing that 'Iron Man 2' can boast is that it's entertaining. In the vast pantheon of iconic movie sequels, it's safe to say that some titles will forever be immortalized in our collective consciousness; obvious national treasures such as 'The Empire Strikes Back,' 'The Godfather Part II' and 'Breakin' 2: Electric Boogaloo' spring immediately to mind.

Will 'Iron Man 2,' which opens Friday, join the ranks of the celluloid untouchables, indelibly etched into our pop cultural landscape for its contribution to film as an art form? Probably not, but one thing that 'Iron Man 2' can boast is that it's entertaining.

While other superheroes are hanging from webs writing emoetry or standing atop a lonely skyscraper and bemoaning their cursed existence, Tony Stark (Robert Downey Jr.) embodies the sheer, childlike glee of what it is to be a superhero. After all, what does a billionaire playboy, who owns the world's coolest chick magnet as a fashion accessory, have to pout about?

As it turns out, more than you'd think. Those sweet red and gold threads aren't quite as eco-friendly as spandex, and all that technology is starting to take its toll on our hero, whose devil-may-care attitude and rampant egomania aren't quite enough to disguise the fact that his swanky suit is slowly poisoning him.

Lucky for us, his impending demise isn't enough to distract Tony from being his usual, cocksure self; from baiting politicians to burdening his long-suffering paramour Pepper Potts (Gwyneth Paltrow) with the fallout from his repeated showboating, Tony Stark is a human wrecking ball equipped with the world's most sophisticated weaponry -- thank god he's got a heart of gold (or is it palladium?) underneath all that metal. Downey imbues the character with such confidence, charisma and comic timing that, even at his most destructive, you can't help but love him -- just wait 'til you see the way he celebrates his birthday.

Now free of the cumbersome origin story that occasionally bogged down the original movie's first act, director Jon Favreau is able to hit the ground running with 'IM2,' honing in on all of the beats that made 'Iron Man' such a smash hit in 2008. The movie is at its zenith when Downey is allowed free reign, attacking every scene with all the manic dynamism of a truly eccentric genius and bantering at a blistering pace that leaves even his most worthy co-stars in the dust.

Speaking of Downey's co-stars ... They say a hero is only as good as his villain, and fortunately our villain is played by Mickey Rourke, who, for the most part, steers clear of the scenery-chewing, mustache-twirling theatricality that plagues many comic book adversaries, opting instead for a more subtle, Machiavellian brand of scheming (in between wrecking race cars and billion-dollar super-suits, that is). Pity his weapon of choice often suspiciously resembles an electrified jump-rope ...

He leaves all the mustache twirling to Tony Stark's rival industrialist, Justin Hammer, played with panache by a smarmy Sam Rockwell. Imitation might be the sincerest form of flattery, but Hammer is the palest imitation of Stark imaginable (right down to the gaudy fake tan smeared all over his palms) and he's well aware of just how far he falls short of Tony in brains, brawn and brilliance. So, like any little man with big insecurity, he embarks on an epic quest of overcompensation; an ego-trip that stands to destroy everything that Tony has built -- and half of the world along with it.

Other new additions to the 'Iron' roster include Scarlett Johansson as Natalie Rushman AKA Natasha Romanov AKA a hot chick in a catsuit (codename: Black Widow, to the purists), who spends most of the narrative looking alternately doe-eyed and lethal. She's not entirely convincing as Tony's sultry secretary, but in full ass-kicking mode, she provides one of the most impressive fight sequences of the movie.

Tony's straight-laced best friend James "Rhodey" Rhodes has undergone reconstructive surgery and now seems to resemble Don Cheadle instead of Terrence Howard, but he's clearly having a blast with the meatier role. Fans of the comics will be enthralled by the two major setpieces involving War Machine -- the sleek, silver version of Iron Man's suit with a few, Hammer-supplied updates -- it's safe to say that he's no sidekick.

If there's one criticism of 'IM2,' it's that too much screen time is devoted to the machinations of the antagonists, which results in a plot that at times feels bloated. But prone to moments of self-indulgence (much like the titular hero himself) or not, once the movie has you in its iron grip, it doesn't let go.

There's no question that the original 'Iron Man' was smarter, but the sequel is an explosive, adrenaline-soaked thrill ride that takes you from zero to 60 in the first 10 minutes and never slows down to breathe. You've never seen a superhero look quite so super until you've seen Iron Man take down a literal army of armored killing machines in an exhilarating chase set high above the streets of New York.

In addition to its regular theater run, 'IM2' also rolls out its 'IMAX Experience' on May 7, and it's well worth the extra couple of bucks to super-size your screening. In IMAX, the action sequences are eye-poppingly, jaw-droppingly spectacular, putting you so far inside the chaos that you'll be dodging debris.

Whether you're a comic book purist or brand new to the franchise, 'IM2' takes you to a whole new level of action, so we advise you to sit back, relax and enjoy the ride -- summer has officially arrived.

(Oh, and make sure you stick around until after the credits if you're Marvel fan, you'll get a "Mighty" surprise. "Avengers Assemble," anyone?)


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