Leonardo Dicaprio likes playing "complicated" characters.

The 'J. Edgar' star insists he never thinks about the type of genre he wants to tackle next in his career path and instead plans his movie choices according to the roles he finds interesting.

He explained: "I've never doubted the material I've been drawn to. I don't do a film because I feel it's time to do a comedy or a science-fiction or another genre.

"I do it because I'm motivated, it interests me, and I feel as if I could be of service to the character. And I like complicated characters."

Leonardo stars as FBI founder J. Edgar Hoover in the drama film and is also working on 'The Great Gatsby' - an adaptation of F. Scott Fitzgerald's classic novel - and has enjoyed the experience of both movies as he was able to do so much research to prepare for the parts.

He added: "Like 'The Great Gatsby', 'J. Edgar' led to a million questions I wanted answered, and it got me excited to research the character."