'Avengers' Trailer Launches Online

Robert Downey Jr., Chris Evans and Chris Hemsworth make their big superhero debut as Earth's Mightiest Heroes.

In 2008, during the final moments of "Iron Man," the world at large became aware of a phenomenon that comic book readers have known about for years when Samuel L. Jackson, dressed eye to toe in S.H.I.E.L.D. director Nick Fury's black leather garb, introduced the concept of "the 'Avengers' initiative."

Fast-forward almost four full years later, and we're nearly there: Earth's Mightiest Heroes are on the cusp of assembling for "Marvel's 'The Avengers,' " and today (October 11), true believers across the globe are getting their first glimpse at the superhero blockbuster's all-star roster in action.

Directed by Joss Whedon and featuring all of your favorite Marvel heroes including Captain America (Chris Evans), Thor (Chris Hemsworth) and ol' Shellhead himself (Robert Downey Jr.), "The Avengers" is poised to be the biggest comic book movie of all time ... and the trailer certainly helps to sell that epic scope.

The "Avengers" trailer, which debuted online at Apple.com, begins with a menacing monologue from familiar adversary Loki, last seen at the end of "Thor" falling into a cosmic abyss.

"You were made to be ruled," he whispers cruelly as shots of carnage and chaos flood the screen, "and in the end, it will be every man for himself."

A quick cut of scenes brings us to Agent Coulson (Clark Gregg) and his boss, Fury, putting their heads together about how best to solve this unknown, ongoing crisis hatched by Loki and his devious plotting. "There was an idea," Fury says, "to bring together a group of remarkable people, so that when we needed them, they could fight the battles that we never could."

Cue those remarkable people: the Asgardian hero Thor, the time-displaced Steve Rogers, the easily enraged Bruce Banner, the eagle-eyed Clint Barton, the deadly Black Widow and, of course, the eternally arrogant Tony Stark. We see these heroes on the battlefield fighting both alongside each other and against one another, showing just how difficult it's going to be for these superpowered warriors to get along.

But even if they can't settle their differences, Stark is looking on the bright side: "If we can't protect the Earth, you can be damned sure that we'll avenge it."

Between Nick Fury launching a bazooka at an unseen assailant and Banner transforming into "an enormous green rage monster," we'd say most of our "Avengers" trailer wishes have been fulfilled. The movie assembles in theaters on May 4, 2012.

Check out everything we've got on "Marvel's 'The Avengers.' "

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