to chime in on spree/serial killers: serial killers are compelling because they are acting out of a sexual compulsion (more often than not) that they have to cultivate into a series of clandestine and intricately planned procedures in order to fully enjoy an illegal, immoral experience. spree killers are socially frustrated, succumbing to social pressures, lashing out instead of conforming to simple rules or adjusting their own perspective. it's about emotional un-fulfillment, rather than sexual control, which is not nearly as interesting.