Thor
Thor is the namesake protagonist and main character of the film of the same name. Played by Chris Hemsworth, Thor is the Norse God of Thunder who was given tremendous power to wield thunder and lightning (with the help of his magic hammer, Mjolnir) when born to King Odin of Asgard and his mother, Frigga.
Thor is Odin's eldest son. Although he is brave, strong, powerful, and incredibly intelligent, he is fairly arrogant and brash, leading to conflicts with the people in his life. In fact, Thor's father becomes so perturbed by his son's arrogance that he sends him to Earth and strips him of his powers. There, Odin hopes Thor will learn how to be humble and learn how to be a true hero. In the end, he hopes Thor learns how to become the future King of Asgard.
On Earth, with the help of his girlfriend, Jane Foster, Thor learns humility and becomes a true hero, saving the Kingdom of Asgard along the way. Thor is revealed to be a kindhearted man who only wants the best for the people around him, especially his family.
Loki
Played by Tom Hiddleston, Loki is the God of Mischief and a renowned trickster. The main antagonist of the film, Loki, is chiefly interested in obtaining power at any cost. To that end, Loki, who feels betrayed that he wasn't told that he was adopted and a descendant of the frost giants, wages war against his adoptive father, King Odin, and adoptive brother, Thor, to take control of the Kingdom of Asgard and all the power associated with it.
While he isn't as powerful as his brother, Loki is able to utilize magic to achieve his goals. He is an angry but exceptionally intelligent man and wants nothing more than to be accepted by those around him (especially his adoptive family).
Odin
Played by Anthony Hopkins, Odin is the longtime King of Asgard. He is considered the All-Father and is Thor's father, Loki's adoptive father. An intelligent and benevolent but stern King, Odin wants nothing more than for his Kingdom to succeed and for peace to be maintained in the Nine Realms. Odin frequently requires Odinsleep to recharge his immense powers (called Odinforce, which grants him the ability to manipulate magic, energy, and superhuman strength).
Jane Foster
Played by Natalie Portman, Jane Foster is Thor's girlfriend and a renowned astrophysicist. She meets Thor after he is banished to New Mexico. There, she and her team are studying strange atmospheric phenomena they have been witnessing across the Earth. Jane Foster is an incredibly intelligent, loyal, and inventive person who values her own independence. She is only critical in Thor defeating Loki.
