AceShowbiz -

Chris Hemsworth has opened up about how Thor returns to Earth to save mankind in "The Avengers". The actor, who will reprise his role as the God of Thunder in the superhero ensemble film, revealed that his hammer-wielding character is summoned from Asgard by his father Odin to stop Loki from creating madness on Earth.

"Thor has conveniently come back to Earth briefly because Odin summons dark powers from the universe and it's very costly," said Hemsworth as quoted by Comic Book Movie. "He's come back to retrieve Loki, who's running madness on Earth and causing a lot of chaos. He also has some questions of his own he wants answered like, 'How did this happen and where did I and my brother go wrong?' "

Hemsworth went on discussing what differs his character in "Thor" and that in "Avengers". He explained, "In 'Thor' my character learned a whole lot about humility and gained a new respect for humans because they were able to help him discover who he needed to become in order to earn his powers back."

"I also think he feels very protective of humans now because of his relationship with Jane," so the Australian actor added. "Joining The Avengers team is also tricky because he has a personal investment in that his brother Loki is the one who's causing the chaos and he fears that the others may just want to kill him instead of just stopping him and taking away his powers."

During the chat, Kevin Feige, Marvel Studios' president of production, also dished on Hemsworth's significance in the upcoming movie. He said, "The reason we cast Chris Hemsworth is we didn't want Thor to just be a one dimensional Adonis-like character."

"What makes a character a Marvel character is that you can relate to them and recognize your own flaws and struggles in the character's flaws and struggles," Feige explained. "In 'Thor' the character has to learn the lesson of humility and Chris was able to bring that in a very likeable way, despite the fact that he comes from another world."

Hemsworth will be joined by Chris Evans, Robert Downey Jr., Tom Hiddleston, Jeremy Renner, Scarlett Johansson and Samuel L. Jackson who will reprise their roles as Captain America, Iron Man, Loki, Hawkeye, Black Widow and Nick Fury respectively. Mark Ruffalo also supports the movie by starring as Bruce Banner a.k.a The Hulk.

Organized by S.H.I.E.L.D., all the famous superheroes must team up to defeat an enemy no single hero could ever withstand. Before opening wide in the U.S. on May 4, the superhero movie is scheduled to close the 2012 Tribeca Film Festival in New York on April 28.