Chris Hemsworth has been cast as the title character in Kenneth Branagh’s big screen adaptation of Marvel’s Thor. Hemsworth will also be playing the mythic comic book character in the Summer 2012 superhero team-up film The Avengers.

You might be wondering, “Who the hell is Chris Hemsworth?” While you might not recognize his name, you saw him on the big screen last weekend in JJ Abrams’ Star Trek as George Kirk. Some of my critic friends had a big problem with Hemsworth’s performance in the opening sequence, but I did not.

Nikki Finke reports that Marvel and Branagh made the final decision earlier today after reviewing Hemsworth’s test footage, which was described as “Oh my god.” Chris is currently in production on the Joss Whedon-written Drew Goddard-directed horror film The Cabin in the Woods. The Australian actor was also just cast as the lead role in MGM’s Red Dawn remake last week.

He’s a virtual unknown in the United States, but he was a star on a successful television series back in Oz (171 episodes of Home and Away) and was on the 2006 Australian version of Dancing with the Stars.

Written by Mark Protosevich, the story has been described as being “like a superhero origin story, but not one about a human gaining super powers, but of a god realizing his true potential. It’s the story of an Old Testament god who becomes a New Testament god”.

Marvel will self-finance the production, and the film will be distributed by Paramount Pictures. Marvel has announced a June 17th 2011 release date for the film.

Discuss: What do you think of Hemsworth as Thor?