Mumbai, India (CNN) -- To say Gregory David Roberts has witnessed much in his life would be an understatement.
The 57-year-old native Australian was sentenced in the late 1970s for a series of armed robberies.
He escaped prison and found his way to Mumbai, India, where he lived for 10 years forging a new life, including work as a doctor in the city's slums.
Roberts' other career highlights? He joined the mafia in Mumbai, fought against Soviet forces in Afghanistan and married a princess.
CNN's Anjali Rao spoke with Roberts in Mumbai, the setting and inspiration for "Shantaram," the novel loosely based on his life. Watch Roberts talk about his life in the slum
A brief excerpt from the interview:
CNN: Is it kind of strange that you used to live here, and you were down to your last pennies I guess, and now when you come back here it's with CNN, or Madonna and Guy Richie. Is it kind of strange the way that your life has just taken that change, that turn?
Roberts: No, I know this sounds strange, but I think it was to be expected. I had a dramatic change that occurred in my life 19 years ago.
I changed the orientation of my life, took control of my life. I think that if you do that, and you stay true to it, and you stay true to a set of principles -- of being fair, honest, positive, and creative in what you do; of pledging not to harm others, and to minimize any amount of harm that you do to other people or to the world around you; you don't take drugs, you don't poison your mind, you don't take alcohol; you focus on what you're doing, keep your discipline -- then I think it's natural that positive outcomes will occur.
There's a sense in which it's a natural progression, from taking control of your life and saying, "I'm going to make my destiny happen. I'm not going to allow destiny to control me, I'm going to control my destiny." I think that we can expect it to happen in those ways, so it's not really a surprise.
The thing is, it's not surprising that I've come to know these people; the surprising thing for me is that they are almost universally nice people. I haven't met anyone at that level -- whether it's Richard Branson, or Johnny Depp, or Madonna, to name a couple -- who are not very, very nice people, and deeply concerned about the world they live in, and trying to make a difference.
And that's the thing that's to me very surprising, I mean and it's a good surprise.