It's a Mystery

[heslopian]

thats up to the beholder more than the artist i think.

Yeah, I get the feeling my question and argument are very subjective. One very deep mystery novel I read was A Game for the Living by Patricia Highsmith, about a wealthy German atheist and a poor Mexican Catholic who come to suspect each other of the rape, murder and mutiliation of a woman they were both having affairs with, but again I felt as though the mystery element was incidental.
By "mystery" I mean your traditional objective problem with a crime and an unkown culprit, as opposed to something metaphysical like Flowers for Algenon (didn't that star Matthew Modine?).