"I enjoyed playing the character but I don't know that I can relate to him. But part of my job is to do what is asked of me in the script and not have to worry about whether it pertains to me or not. You don't have to actually shoot heroin to play a drug addict, you know," he added.
Clooney also admits he fears repeating the same career choices over and over again.
"My biggest fear is doing the same things 10 years from now. That would be a failure. It's something you have to constantly reassess, and asking yourself what you are going to do next makes it a good long full journey," he added.