The 30-year-old actor - who began his showbusiness career as a member of the `All-New Mickey Mouse Club` when he was 12 years old - wants to try other things in his life but doesn`t yet know when he will end his career.
He said: "I`ve been doing this since I was 12. I don`t want to act much longer. I can`t do one thing my whole life. I know there are only so many characters I`ll be able to play. It will be over whenever the inspiration dries up."
Ryan can next be seen in `Drive`, and while the violence in the film has caused some controversy, Ryan loves the disturbing scenes and finds them "fascinating".
He added in an interview with The Times newspaper: "You make movies to fill a giant screen. I was it with people who screamed and cheered like at a soccer game. They weren`t sure if it was a joke. "Were we serious? It was so violent we had to be, but it was so violent how could we be?
"I love the violence. It`s fascinating how primal it is. We didn`t really concern ourselves with its authenticity. It was more of a symbol of my character`s emotional landscape."