Nothing like The Avengers has ever been attempted in Hollywood history.  No major motion picture has ever been the culmination of four different blockbuster franchises, each with its own protagonist, and crossing them over into one gigantic film.  It's bigger than a sequel or even a planned trilogy.  Marvel had to take pieces from their previous superhero films to assemble The Avengers.  The studio wedged set-up into Iron Man 2, wove the covert government agency S.H.I.E.L.D. into Thor, and tacked bookends to Captain America: The First Avenger.  The plan for The Avengers was audacious to the point of near-hubris, but writer-director Joss Whedon has managed to deliver an absolute powerhouse of a payoff that's truly worthy of Marvel's astonishing ambition.

After being exiled from Asgard, the villainous demigod Loki (Tom Hiddleston) makes a bargain with a shadowy, malevolent entity.  Loki must go to Earth, capture the fabled Tesseract (a cosmic cube of immense power), and use it to open a portal that will allow the alien Chitauri army to invade our planet and make Loki our ruler.  S.H.I.E.L.D. has the cube, but Loki quickly takes it along with agent Clint Barton aka "Hawkeye" (Jeremy Renner) and Dr. Erik Selvig (Stellan Skarsgård) by using a mind-controlling scepter.  Barton has access to S.H.I.E.L.D. resources, Selvig has the science to open the portal, and the only ones who can stop Loki's plan are Earth's mightiest heroes: Tony Stark aka "Iron Man" (Robert Downey Jr.), Thor (Chris Hemsworth), Natasha Romanoff aka "Black Widow" (Scarlett Johansson), Bruce Banner aka "The Hulk" (Mark Ruffalo), and Steve Rogers aka "Captain America" (Chris Evans).

Iron Man, Iron Man 2, Thor, and Captain America all provided an essential ingredient in helping the plot of The Avengers by allowing it to skip character introductions.  Thor and Captain America get a couple brief moments to recap the key events of their movies, but The Avengers doesn't waste time with exposition.  Instead, the film devotes most of its energy to bringing a bunch of superheroes together and expanding their individual stories.

Writer-director Joss Whedon does a wonderful job of taking the characters other people built, staying true to their personalities, and then adding his unmistakable spin.  Captain America in The Avengers is essentially the same pure-hearted, unflappable do-gooder from Captain America: The First Avenger, but through Whedon, we get a character emotionally struggling to adjust to being ripped out of 1944 and awakening over sixty years later.  At the same time, Whedon still has the good comic sense to let the character get giddy at recognizing a pop culture reference.

Almost every character gets this strong blend of comedy and drama.  Thor provides the emotional grounding for Loki, who would simply be a moustache-twirling supervillain without his superhero half-brother.  Black Widow gets plenty of screentime to expand her individual story to the point where it feels like a heavy prep for a great spin-off.  As for Hulk, The Avengers manages to deliver the best on-screen adaptation of the character.  In addition to having the Hulk kind of look like Mark Ruffalo, this is the first time the Hulk is actually fun.    Whedon and Ruffalo turn Banner away from the brooding loner, and turn him into a bashful, nerdy guy who will only acknowledge the Hulk as "The Other Guy."  In The Avengers, The Hulk is Chekhov's Gun if Chekhov's Gun were a howitzer tank.  When that blast finally goes off, we see the Hulk realized in the best way possible.

However, Whedon can't quite shower everyone with this lavish attention and development.  Robert Downey Jr. has so thoroughly defined the character of Tony Stark that no one, not even a writing master like Whedon, can leave an imprint.  S.H.I.E.L.D. Director Nick Fury (Samuel L. Jackson) has been a presence in all the previous Marvel movies, but he still doesn't get to be the all-out badass we've been itching to see.  As for Hawkeye, he spends half the movie being Loki's slave, so there's not much room to build a character.

Despite the varying levels of development, The Avengers succeeds on a character level because the story is about bringing these superheroes together.  It's an absolute joy to see these distinct personalities play off each other.  When Iron Man fights Thor, it's not just a geeky thrill to watch the showdown, but to also see how each hero retains their noble intentions while having a genuine conflict.  Whedon operates with an understanding of how someone with the unshakable morality of Steve Rogers is going to handle a wild card like Tony Stark, or how Thor's arrogance hasn't completely diminished since his solo movie.  However, one of the film's few flaws is jumping into some of the conflicts without providing an adequate set-up to the scene.  The second act of the film lacks the flow to move from conflict to conflict so the arguments feel slightly manufactured even though Whedon has stayed true to the characters.

The movie may stutter a bit in the middle, but when The Avengers swings into the third act, it becomes a blockbuster picture at its finest.  Joss Whedon has absolutely realized the geek dream we've been waiting for since Nick Fury introduced himself to Tony Stark after the credits of Iron Man.  The scope of the final battle makes it perfectly clear that no individual superhero could handle this challenge solo.  More importantly, the battle had to be constructed so each superhero was a valuable addition.  The film's climax needs Iron Man's speed, Captain America's on-the-fly tactics, and Hulk as the unstoppable weapon.  Every superpower is an instrument in Whedon's grand symphony of delightful destruction.

The opening set piece raises doubts about Whedon's ability to direct action since it's difficult to tell where characters are in relation to each other, but after this initial misstep, the action scenes are an absolute blast.  Whedon swooshes his camera around the battlefield, embraces the magnitude of the situation, and makes the audience feel every hit.  The 3D provides a little bit of depth to the climactic finish, but the effect doesn't add much to the overall picture.  The third act of The Avengers bears a resemblance to Transformers: Dark of the Moon, and while Michael Bay has a greater mastery of 3D, Whedon has mastery over creating a coherent narrative featuring characters you care about.   I'll always take the latter over the former.

Leading up to The Avengers, every director had left a stamp on their Marvel movie, but not to the point where he was inseparable from the material.  Kenneth Branagh provided a fantastical grandeur to Thor (along with superfluous canted angles) and Joe Johnston imbued Captain America with an old-fashioned, patriotic vibe.  These are styles, and they can be recreated.  But there is only one Joss Whedon, and The Avengers wouldn't be as strong without him.  He understands how to develop meaningful relationships between his characters, has a surprising talent for crafting epic action scenes (a welcome surprise considering his only feature film before Avengers was the modestly budgeted Serenity), and his humor is second-to-none.  There are some one-liners and visual gags that still have me giggling when I think about them.

The Avengers is why we go to the movies.  The film will work fine on a big-screen TV, but it's the kind of gigantic blockbuster fare that sends us back to every summer we went to the theater and were absolutely wowed.  By crafting a winning combination of wonderful characters, brilliant comedy, and spectacular set pieces, Whedon hasn't simply created the biggest superhero movie; he's created one of the best.

Rating: A-