Chris Hemsworth knew little about 'Thor' when he auditioned for the lead role.

Despite knowing "nothing" about the film and only having time to "rip through a couple of comic books", the 26-year-old star managed to beat his brother Liam for the title role of the Norse warrior God.

Speaking at the Comic-Con event in San Diego, the Australian actor told MTV News: "The very first audition I had was one of those things in amongst several other auditions you get. You know nothing about it, there's no script or anything - it's very secretive. You might quickly rip through a couple of comic books, but it's also based on instinct."

Chris also claims despite auditioning against his brother - who dates teen star Miley Cyrus - there was no sibling rivalry.

He explained: "No, it's great. The majority of the time in this business, we're sort of pinching ourselves."

"I'm excited for him and vice versa. Through that process, I was giving him advice on what I thought Ken wanted - and then when I was in there testing, he was doing the same."

Meanwhile, the director has revealed that it was an "exhaustive search" to find the perfect Thor.

Kenneth told "When Chris came in for the final audition we knew he was the guy. He nailed it."

The movie will also feature Rene Russo as Frigga, Thor's mother, Anthony Hopkins as Norse god Odin, Tom Hiddleston as the villain Loki and Natalie Portman as Thor's love interest.

'Thor' is due to be released in 2011.