In the introduction to her book, A Moment on the Edge: 100 Years of Crime Stories by Women, Elizabeth George, the creator of the Inspector Lynley mysteries, asks why crime, and especially murder, is so important, not just in mysteries, but in books of many kinds: thrillers, exposes, and non-generic literature. She points out that fascination with violent subjects goes at least as far back as Biblical times. The characters in the Old and New Testaments regularly kill, commit adultery and worse (e.g. incest), and betray those around them.
“Crime is mankind on the edge, in extremis, but more than that, crime is mankind stepping outside of the norm. For every Cain, there are a billion brothers who have co-existed throughout the centuries. For every David, there are ten million men who’ve turned away from a woman they want when they learn she is committed to another. But this is what makes crime so interesting. It isn’t what people normally do.”
As George points out, the eruption of violence into what is normal puts the characters in a fiction to the test. This is the stuff of drama and catharsis.
Another answer to the question I posed in my June 23 post: does it have to be murder?