The third film in the Marvel Cinematic Universe introduces the Norse god of thunder and unleashes him on the Earth.

The film starts with Jane and her group of scientists driving around a desert looking for magnetic storms. The one they find is a lot stronger than they expect and they run over a stranger that suddenly appears in their path.

We then get a history lesson, on how the gods of Asgard helped fight off an invasion of the frost giants on Earth centuries ago, defeating them and stealing their power source before forcing them into a truce. Fast forward to today and Thor is about to be named king when a small group of frost giants attacks, attempting to steal the power source back, only to be thwarted by the Destroyer. Odin is troubled but happy that the threat is passed, but Thor is livid that the giants would dare to attack, and determined to find out their plan and put them in their place, despite Odin forbidding it.

Thor gathers up his group of warriors, including jealous brother Loki, and heads off to the ice giant world regardless. This expectedly ticks the giants off and a battle breaks out, forcing Odin to come to rescue them, and causing the ice giants to declare war. During the fight Loki is touched by one of the giants, but doesn’t freeze, which concerns him. Back in Asgard, Odin is furious with Thor for his actions. He takes his power away, putting it in Thor’s hammer for whoever is worthy to wield it, and banishes Thor to Earth, throwing the hammer in after him. He crash lands on the other side and is promptly hit by the scientist’s truck, bringing us back to the introduction. They taze the confused god and toss him in the back for transport to the hospital while they go off to examine their data.

Thor has a few mishaps with hospital staff before sneaking out of the hospital just as Jane and co. realize he came from the anomaly they are studying and decide to go back to question him, leading him to get run over a second time before they bring him back to their apartment. Meanwhile, the hammer has been garnering some attention as no one can seem to lift it, and crews are having a party trying to do so before SHIELD shows up and locks the area down.

Back in Asgard the Thorettes find out that Loki had sent word to Odin about Thor going to see the ice giants and feel betrayed. They start to wonder if Loki set up the attack on the vault in the first place. Loki heads into the vault himself to see the power source and discovers from Odin that he is actually the son of the ice giant king, and his anger at learning this literally gives Odin a heart attack.

Meanwhile a hungry Thor hits up a diner and overhears people talking about his hammer, so he takes off to retrieve it. He asks Jane for a lift and she refuses, so the scientists leave to find that SHIELD is taking their equipment and data.

The Thorettes go to see Odin to ask for Thor’s return, only to find that Loki is now in charge as Odin recovers. Loki refuses to undo Odin’s last order and sends them away.

Jane changes her mind about taking Thor to the crash site, determined to get her research back. They approach the SHIELD compound that was built around the hammer, and Thor goes to infiltrate on his own, fighting his way past the guards, impressing a watchful Hawkeye and finally reaching the hammer only to find that he cannot lift it. Depressed and defeated he allows the agents to take him.

Coulson interrogates Thor and gets nowhere, but Loki arrives and lies to Thor to tell him that Odin is dead, and that Thor will never be allowed to return to Asgard. His visit is soon followed by Eric Selvig, Jane’s scientist friend, who manages to convince SHIELD to release him, and steals back some of the data. Thor and Jane bond over science as he explains his land.

Meanwhile Loki makes a deal with the ice giants to let them take Asgard, admitting that he was responsible for the original breach, and he forbids the path between worlds from being opened, but the Thoretts work with Heimdal the gatekeeper to travel to Earth anyway to look for Thor. Loki catches wind of this and sends the Destroyer after them, freezing Heimdal in the process. The Destroyer blows up a number of SHIELD vehicles and threatens the town. The Thorettes attempt to fight it off while Thor and Jane get the people to safety, but they are no match for it. Thor decides to sacrifice himself to end the onslaught, but in the process in finally deemed worthy to wield the hammer, and his power is restored and he is able to use it to defeat the Destroyer.

Loki welcomes the ice giants into Asgard as Thor approaches the gate, and Heimdal is able to break free to let him and the Thorettes return home and attempt to stop Loki. The ice giant king attempts to kill Odin, and Loki kills him in return, making him look like a hero and giving him an excuse to attack the ice giant’s realm using the bifrost gate. Thor engages him, trying to stop him. He defeats Loki, but the only way to shut down the bifrost is to destroy it, cutting him off from returning to Earth, and sending Loki off into the abyss between worlds.

Thor realizes that he is not ready to become king and still has much to learn as Asgard attempts to return to normal, and Jane continues to search for a way to bring Thor back.

In the post credit scene we see Nick Fury recruit Dr. Selvig to investigate a potentially unlimited power source. Selvig accepts, with a little hidden encouragement from Loki.

TLDR: Norse god Thor is sent to Earth to learn he isn’t all that and his brother Loki attempts to take over Asgard.