Contrary to what many writers imply about the process, nobody forces a writer to sell his work to the film industry.
I don't think the problem is that people don't read enough mystery books, but that people don't read.
I do like to explore evil characters in my books.
When I write a book, I'm making it the best book I can.
Much of what we do in life has a huge component of luck.
But at the same time, the commonplace statement about them is true: every character is the hero of his own story. Each has a justification for his actions that is convincing to him. It's fun to give these people voices.