Avengers Assemble

During an evacuation, S.H.I.E.L.D. (Strategic Homeland Intervention, Enforcement, and Logistics Division) director Nick Fury (Samuel L. Jackson) makes his way to the organization's headquarters outside of Santa Fe, New Mexico. An unidentified energy source, the Tesseract, has begun to function. The exiled Norse deity Loki (Tom Hiddleston) enters the portal through space carrying an odd spear with a blue flashing point.

To help him escape, Loki uses the Tesseract and the spear to take over the minds of many SHIELD employees, including Agent Clint "Hawkeye" Barton (Jeremy Renner) and Dr. Erik Selvig (Stellan Skarsgrd). When an energy burst from the Tesseract causes the ground beneath the facility to collapse, forcing it to be destroyed, SHIELD personnel leave their base. Loki is not captured after a brief pursuit.

As a result of the assault, Nick Fury declares a state of emergency and informs his top agents Maria Hill (Cobie Smulders), Natasha Romanoff (Scarlett Johansson), and Phil Coulson (Clark Gregg) that they have run out of alternatives. Romanoff and Coulson are sent to look for the heroes he needs to fight Loki when Fury yanks them from their respective tasks.

Coulson removes Romanoff from the task and instructs her to find "the big guy": Bruce Banner (Mark Ruffalo), a.k.a. The Incredible Hulk, after discovering her questioning suspects in Eastern Europe. While living in exile in India, Banner has discovered inner peace by assisting sick patients at a hospital in Calcutta. Banner is informed by Romanoff of the Tesseract's devastating potential. They stand the best chance of locating the cube thanks to Banner, the foremost authority on gamma rays.

Fury is questioned about his strategy for implementing the Avengers Initiative during a video conversation with the World Security Council, the administrators of S.H.I.E.L.D. The WSC is outraged, claiming that it is unacceptable to act in this way and that these individuals will never cooperate as a team. Fury claims that this is their only chance to beat Loki and that they have no other choice. The higher-ups reluctantly concur.

On the other side, Steve Rogers (Chris Evans) is quite simple to track down. Since he was found alive in the ice, S.H.I.E.L.D. has been keeping an eye on him. Fury discovers Rogers is awake as he goes to meet him in his gym. Rogers is informed by Fury that he will discover a briefing packet regarding the situation back at his apartment. Robert Downey Jr.'s Tony Stark can be seen wearing a new Iron Man suit with underwater capabilities.

He is putting in a new electrical connection that will entirely disconnect his office building from the power grid, enabling it to become self-sufficient. He is welcomed by Pepper Potts (Gwyneth Paltrow), who informs him that it is date night, at his workplace. Date night is cancelled following a disagreement about how much credit Pepper should receive for coming up with the concept for the Stark Tower. Tony wants Pepper to understand what it's like to be a genius. Tony immediately and repeatedly tries to cut Coulson off as he approaches.

Tony receives a laptop from Coulson that contains all the information regarding what is happening. Tony seems to have a lot of research to do, so Pepper chooses to travel to Washington, DC, to obtain the zoning permits for the next two Stark Tower structures.

Coulson tells Rogers about his Captain America trading card collection as they fly to the secure site, an aircraft carrier that can transform into a flying aircraft carrier, and how it's such an honour that they found him. Rogers meets Dr. Bruce Banner before they continue to the helicarrier. The two then ponder the nature of the journey ahead. Rogers believes it to be a submarine, but Dr. Banner has no business travelling in a pressurised, submerged metal container. The transporter lifts off. They learn on board that Stuttgart, Germany is where Dr. Selvig and Loki were found.

The first task given to Rogers is to travel to Stuttgart in order to detain Loki and transport him to the helicarrier. Loki is abducting a doctor who possesses the element required to make the Tesseract function while he is at a sophisticated black tie banquet held at an art institution. Loki executes his plan while Dr. Selvig makes a distraction and Hawkeye kills the guys guarding the building. He is telling the civilians outside that freedom is the greatest deception in life and that they must kneel before him or else.

One elderly guy does, though, and Loki is about to kill him because of his stubbornness. Before advancing to confront the deity, Rogers as Captain America successfully deflects the fatal shot with his shield. With full Iron Man weapons drawn and a challenge to Loki to act, Tony arrives as Rogers fights Loki to the sound of AC/"Shoot DC's To Kill."

When the two heroes arrive, Loki swiftly gives up, and as he is being transported to the cutting-edge jail aboard the helicarrier, the aircraft runs into a lightning storm. Loki replies that it's not the lightning that he's frightened of when Rogers asks if he's afraid of lightning. It is what comes next.

Loki's half-brother and Norse God of Thunder Thor (Chris Hemsworth) shows in and makes an attempt to kidnap Loki so that he can face Asguardian justice for his crimes, which will be more effective than Earth's, but Thor fights with Rogers and Tony. There is no winner in this conflict. Loki is eventually transported to the helicarrier and put in a glass cell that was made to house the Hulk. Fury warns that if Loki tries to escape, even just by breaking the glass, a shaft will open beneath him, sending him falling to Earth where he may perish.

Fury is giving a briefing to the whole Avengers team aboard the aircraft carrier regarding what they believe may occur next. Agent Romanoff questions Loki while he is being held captive. When Tony Stark shows up, it appears that Bruce Banner is the only member of the group with whom he actually gets along.

Stark wants to elicit a rise out of Banner while working on Loki's sceptre so he can see Banner's well-known party trick (read: turning into the Incredible Hulk). Banner flinches before explaining that he hasn't been able to use all of his talents and that he developed depressed following the accident. He relocated to Calcutta because he believes that assisting others gives his life purpose.

Now gathered again, the Avengers debate and consider how to deal with Loki and Rogers' finding that SHIELD intends to use the Tesseract's abilities to create weapons.

Fury acknowledges that SHIELD was made aware of other races on other worlds, some of which may view Earth as an easy target, as a result of the events in New Mexico a year prior (recounted in Thor (2011)). Agent Coulson is shown being questioned by Thor regarding Jane Foster's fate. Coulson informs him that she has been placed in S.H.I.E.L.D.'s witness protection programme and is currently in a safe area in London.

The choice was made to create Tesseract-powered weaponry as a deterrent. Clint Barton and Loki's possessed agents attack the helicarrier as the group debates, crippling one of its engines while it is in flight. Romanoff attempts to stop Dr. Banner from transforming into the Hulk and destroys the ship from within while Stark and Rogers try to restart the damaged engine. Her attempt is unsuccessful, and she is then pursued throughout the ship until Thor steps in to help calm the beast and briefly knocks him out with a blow from his hammer, Mjolnir.

Romanoff knocks Barton into a guard rail while fighting him, which ends Loki's mental control. Thor is deceived into Loki's holding cell when the Hulk falls from the ship. Loki, who has found his sceptre, then releases the cell and lets Thor fall. Agent Coulson manages to temporarily contain Loki, but Coulson is also duped by one of Loki's holographic representations, and the real Loki stabs Coulson in the back.

Later, using a mysterious device that taps into the power of the Destroyer, Coulson uses a blast to kill Loki. Fury tries to save Coulson, but Coulson loses his life. Just as the cell hits the ground, Thor escapes from it. After colliding with a deserted factory, Banner awakens in his human form.

Coulson's supposed demise serves as a catalyst for the Avengers to unite under Fury. Stark and Rogers are aware that Loki will be hard-pressed to be defeated by them alone. In order to prove his authority as ruler of Earth, he must defeat them in a highly visible manner.

Loki establishes a connection to the Chitauri home world over Manhattan with a technology created by Dr. Selvig, causing a Chitauri invasion. Once more, the group's little disagreements obscure their capacity for teamwork, especially given that Banner is no longer present. Tony suddenly understands that Loki is a full-on diva and that he has plainly established himself at the top of Stark's office after a dispute with Rogers.

Unfortunately, Natasha arrives too late, just as Dr. Selvig is about to open the portal. All hell breaks loose as a result of Loki's army being released. They can't all fend them off because of the army's size and the speed at which they are infiltrating the atmosphere. Thankfully, Bruce Banner and Tony Stark also appear.

Rogers sends NYPD officers to direct them into the sewers and underground tunnels while they are fighting. In the meantime, the Hulk smashes, and Tony makes his way to Stark Tower where he tries to intimidate and threaten Loki with a drink. In the meantime, Tony instructs JARVIS to create MK18, a prototype version of Iron Man with superior weaponry that is housed in a massive box that was coded exclusively for Tony.

As long as the people of Earth don't understand that they need to be dominated by him, says Loki, the destruction will go on. Tony Stark's fairly reliable Arc Reactor, which keeps him alive, foils Loki's effort to seize control of him by putting his sceptre on his heart to control his thoughts.

The Avengers unite to defend New York, but rapidly realise that they will be outnumbered as the Chitauri advance in waves against Earth. While Dr. Banner changes into the Hulk and chases Loki, defeating him in Tony Stark's penthouse, Rogers and Thor rescue people with assistance from the changed Barton.

Dr. Selvig is released from Loki's control when Romanoff, with a little assistance from the Chitauri, makes her way to the device keeping the portal open, which is conveniently positioned on the roof of the Stark Building. Loki's staff can be used to close the portal, according to Dr. Selvig.

During that time, Hulk confronts Loki, who doesn't back down in the face of such a monster. The Hulk smashes Loki into almost complete nothingness as Rogers directed. That makes it possible for Romanoff to take the sceptre and go to the roof to close the gateway.

Stark is protecting the perimeter while Romanoff secures the portal. While speaking to the council on a conference call, Fury criticises their choice to fire a nuclear missile against Manhattan. Fury uses all available means to prevent the council from launching nuclear weapons, even damaging two jets that are preparing to take off from the helicarrier. Unfortunately, it escapes and fires a nuclear missile just as he is ready to shoot at the third.

When Tony intercepts the missile, he immediately knows where to send it: into the portal. Stark gives JARVIS the order to give Pepper one last try while they are in the vortex. The call is unsuccessful, sadly, because Pepper is on a plane watching TV with other Stark Industries executives. Tony detonates the nuclear weapon at the Chitauri mothership, ending the invasion completely. All of the alien invaders break down and become ineffective. Stark witnesses the nuclear explosion as he is about to lose consciousness and fall to what seems to be certain death.

Fortunately, he escapes the portal just in time for Romanoff to successfully shut it. When Tony is in the atmosphere again, it appears as though he won't survive, but the Hulk saves him with impeccable timing. When the Hulk's roar rouses a sleepy Stark, he offers to take the team out for shawarma, but they opt to capture Loki first. The Avengers depart in different directions. Tony and Pepper are seen reconstructing Stark Tower and are working on the following stage of the project as Romanoff, Rogers, and Hawkeye return to their jobs with S.H.I.E.L.D.

Loki is brought back to Asgard by Thor, where he is put on trial for war crimes by both Asgard and the Chitauri. While numerous TV news stories recap the events involving the Avengers, some people view them as global heroes for their work in New York, while others are afraid and want to know who will be held accountable for the destruction.

Fury receives praise during a subsequent video conference call with the World Security Council, but they also question him about how dangerous this group is now that their identity has been revealed. Fury is relieved because what happened in New York serves as a caution.

All galaxies are being warned that S.H.I.E.L.D. is prepared to protect the earth if they attempt an attack. They just have the team. The S.H.I.E.L.D. board is also informed by Fury that the Avengers' whereabouts are no longer being monitored. Although they are entitled to a leave of absence, they will be called back when necessary. He also informs the council that no one will ever be able to locate the Tesseract on Earth.

In a scene during the credits, the Chitauri leader The Other advises his master against attacking Earth because going up against the Avengers is like courting death. When his master turns, he reveals himself to be Thanos, a worshipper of the embodiment of Death who is gleeful at the prospect of courting her with further human casualties.

After more credits, the Avengers are seen eating together in a shawarma restaurant; the group is silent and appears to be exhausted.