In order for a long piece of work to engage a novelist over an extended period of time, it has to deal with questions that you find very important, that you're trying to work out.
I'm not sure whay I've been drawn to this subject, except that murder is a subject that has always drawn people for as long as people have been telling stories.
I believe, in a funny way, the job of the novelist is to be out there on the fringes and speaking for an experience that has not really been spoken for.