The actor, who also produces the surfing film, revealed that he wanted to become more involved in Chasing Mavericks as he felt so moved by the "emotional and inspiring" story.
"I love to be able to produce, especially if it's a project that you really believe in, and this was very much a passion project for me. When you're producing, you have a chance to get even more involved and have more of a say in the creative process at all levels actually, that's what got me about it," Butler explained to MTV News.
"But from the second I got the script and I read it, one, it's a very powerful and emotional and inspiring story, but two, it really dives into the psyche and the danger and the courage in the sport of surfing and that was something I'd never really seen before in a major feature film. I thought, I want to be part of telling that story. It would be an honour for me to step in there and really try and represent what goes on in the mind and heart of a big-wave surfer."
Butler also promised that fans would be getting more than a stereotypical surfing movie as Chasing Mavericks employed new technologies and techniques while shooting.
"I mean, it is edge-of-the-seat stuff. It's enthralling, takes your breath away, and it's incredible edgy considering this type of movie. They use all kinds of processes and inventions that they've never used before while filming surfing, so we got just the best footage," he said.
"If it was just a surf video, it would be a huge success in that alone, but fortunately on top of that we have a very powerful and compelling story. I've never seen a movie like this, and I felt that when I read the script."
Butler recently ruled out appearing in the sequel to 300, admitting that it "wasn't really [his] thing".
Watch the trailer for Chasing Mavericks, which is released on October 26 in the US and November 2 in the UK, below: