Synopsis for The Avengers

S.H.I.E.L.D. Director Nick Fury (Samuel L. Jackson) arrives at a remote S.H.I.E.L.D. facility during an evacuation. The Tesseract, an energy source of unknown potential, has activated. It opens a portal through space and the exiled Norse god Loki (Tom Hiddleston) steps through. Loki takes the Tesseract and also takes control of the minds of several S.H.I.E.L.D. personnel, including Dr. Erik Selvig (Stellan Skarsgård) and Agent Clint "Hawkeye" Barton (Jeremy Renner), to aid him in his getaway. As S.H.I.E.L.D. personnel pull out of their base, some pursuing Loki and others merely fleeing, the ground beneath the base collapses and it's destroyed.

In response to the attack, Fury re-activates the Avengers Initiative. He pulls Agent Natasha Romanoff (Scarlett Johansson), a.k.a. the Black Widow, out of an interrogation and sends her to India to find and recruit Dr. Bruce Banner (Mark Ruffalo), a.k.a. the Hulk. At the same time Agent Phil Coulson (Clark Gregg) approaches "Iron Man" Tony Stark (Robert Downey Jr.) and requests that he review Dr. Selvig's research. Fury himself approaches Steve Rogers (Chris Evans), a.k.a. Captain America, with an assignment to retrieve the Tesseract from Loki. During his exile, Loki encountered the Chitauri, an alien race seeking to conquer the galaxy. In exchange for the Tesseract, the Chitauri agree to help Loki subjugate Earth.

Suiting up, Captain America and Iron Man travel to Germany to apprehend Loki, who is recovering iridium needed to stabilize the Tesseract's power, and demanding that the civilians kneel before him. Loki quickly surrenders when the two heroes arrive, and he is escorted to a S.H.I.E.L.D. helicarrier, a high-tech, flying aircraft carrier. However, Thor (Chris Hemsworth), Loki's half-brother and the Norse God of thunder, arrives and attempts to free Loki so he can reason with him on his own, but he gets into a fight with Iron Man and Captain America. Eventually, Loki is taken to the helicarrier and placed in a glass cell designed to hold the Hulk.

The Avengers, now brought together, argue and deliberate over how to approach Loki and the revelation that S.H.I.E.L.D. plans to harness the Tesseract's power to develop weapons. Fury admits that the events in New Mexico a year before (recounted in Thor) made S.H.I.E.L.D. aware of other races on other worlds, some of which may see Earth as an easy target. The decision was made to produce weapons with the Tesseract as a means of deterrence. As the group argues, Clint Barton and Loki's possessed agents attack the helicarrier, disabling one of its engines in flight. As Stark and Rogers attempt to restart the damaged engine, Thor tries to prevent Dr. Banner from turning into the Hulk and destroying the ship from inside. While fighting Barton, Romanoff discovers that a blow to the head powerful enough to knock Barton unconscious will break Loki's mind control. By the end of the battle, Loki escapes, Thor and Dr. Banner have been ejected from the ship and Agent Coulson is killed.

Fury uses Coulson's death to motivate the Avengers to work as a team. Stark and Rogers realize that simply defeating them will not be enough for Loki. He needs to overpower them in a very public way so as to validate himself as ruler of Earth. Using a device built by Dr. Selvig, Loki opens a portal to the Chitauri home world over Manhattan, summoning a Chitauri invasion.

The Avengers rally in defense of New York, but quickly come to the conclusion that they will be overwhelmed as wave after wave of Chitauri descend upon Earth. With help from the reformed Barton, Captain America and Thor evacuate civilians while Dr. Banner transforms into the Hulk and goes after Loki, beating him into submission in Tony Stark's penthouse. Romanoff makes her way to the device that holds the portal open (conveniently located on the roof of the Stark Building) and hits Dr. Selvig over the head, freeing him of Loki's control. Dr. Selvig reveals that Loki's staff can be used to close the portal.

Meanwhile, the directors override Fury and scramble a jet that fires a nuclear missile at Manhattan to end the invasion. Iron Man intercepts the missile and directs it at the portal and the Chitauri base before running out of oxygen and plummeting back to Earth, but the Hulk catches him as he falls. Thor escorts Loki and the Tesseract back to Asgard, while Fury notes that the Avengers will go their separate ways until such time as a new world-threatening menace emerges.

In a post-credits scene, the Chitauri leader the Other tells his master that it is futile to attack Earth, as fighting the Avengers is like courting death. His master turns, revealing himself to be Thanos.

Sumber : http://www.imdb.com/title/tt0848228/synopsis